How To Choose Optional subject combination for IFoS Mains 2020

Updated On -

Jul 6, 2020

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Optional papers are designed to test your expertise on specific subjects that are chosen by you. This means, when you are choosing an IFoS optional subject, you will be expected to have in-depth knowledge about it. The choice of optional is crucial as it affects your overall marks in Mains as well as influences the kind of questions you will be asked in the interview round. It is not always necessary to choose an optional subject that was in your academic curriculum. But at the same time, you should be confident about your preparation of an entirely new subject. There are so many different perspectives to think about while choosing optional papers and hence, it should be done very carefully.

List of Mains Optional subjects in IFoS Mains

The first and foremost task is to know thoroughly the list of optional subjects that are available for IFoS aspirants. Unlike other UPSC exams, in IFoS, there are some limitations about the combination of optional subjects that you can choose and you must keep that in mind as well.

  1. Agriculture
  2. Agricultural Engineering
  3. Animal Husbandry & Veterinary Science
  4. Botany
  5. Chemistry
  6. Chemical Engineering
  7. Civil Engineering
  8. Forestry
  9. Geology
  10. Mathematics
  11. Mechanical Engineering
  12. Physics
  13. Statistics
  14. Zoology

Rules regarding optional subject combination in IFoS Mains

The following are the few combinations of subjects that cannot be chosen in IFoS mains as your two optional topics-

  • Agriculture and Agricultural Engg.
  • Agriculture and Animal Husbandry & Veterinary Science.
  • Agriculture and Forestry.
  • Chemistry and Chemical Engg.
  • Mathematics and Statistics.
  • Only one of the engineering subjects, that is- Agricultural Engineering, Chemical Engineering, Civil Engineering and Mechanical Engineering can be chosen as optional
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Factors to consider while choosing the Optional

When you are choosing an optional subject, there are a few important factors that should be noted as the choice cannot be altered later.

  • The chosen subject should have a proven record of being scoring- this will help to boost your ranking up in the final merit list.
  • The availability of books, online resources, readymade notes and other materials for the subject.
  • The length and magnitude of the syllabus and whether it is easy to prepare or time-consuming.
  • Success rate of the subject and availability of coaching and guidance for it.
  • Your personal comfort zone regarding understanding and enjoying the study of the subject.

Subject-wise Pros and Cons of IFoS optional

Based on the factors shared in the previous section, we will individually look into the pros and cons of the different subjects that you can take up for IFoS optional-


  • Agriculture is fairly scoring.
  • There are many good quality study materials available for the subject readily as it is taught in many national universities.
  • The syllabus is short compared to the other optional subjects.
  • There are few coaching centers but numerous detail-oriented online guidance available for the subject.
  • This is one of the optional subjects with the maximum success rate in IFoS. Many agriculture graduates get a place in the final merit list as well as many non-agriculture graduates do so too.

Animal husbandry and veterinary science

  • This is also a very scoring optional subject.
  • Materials are not abundant but not scarce either. The subject is available for graduation in many colleges all over the country and hence a standard is maintained for books and readymade notes.
  • The syllabus is considerably lengthy.
  • This is again a subject on which you will not find many coaching centres but online guidance is available through different education portals, YouTube and blogs of successful IFoS aspirants.
  • The success rate is moderate to good for this particular subject.


  • The marks fetching ability of chemistry is average.
  • You can find some really good materials and reference books for chemistry as it is an established science subject that is taught in most national universities.
  • However, the syllabus is rather lengthy.
  • Coaching and guidance for chemistry optional is available in abundance owing to the popularity of the subject.
  • It is also one of the top subjects with a high success rate as many graduates of chemistry eventually make it to the final merit list with this subject as an optional.


  • Botany is a highly scoring subject, making it a popular choice for optional.
  • There are many books and ready-made notes that are readily available for the subject as it is one of the core science subjects taught in most national colleges and universities.
  • The syllabus of botany is moderately lengthy.
  • There is a fair amount of coaching and guidance available in this subject which is a very common choice of subject for many science students for graduation.
  • This is one of the most successful optional papers and many botany and zoology graduates who have taken it up get selected for the final list every year.

Civil engineering

  • Being a thoroughly technical subject, civil engineering is highly scoring if your preparation is up to the mark.
  • There are an abundance of materials available in the market as it is a core engineering subject taught at almost every technical university and college.
  • The syllabus is moderately lengthy compared to other optional subjects.
  • There are many coaching centres and guidance for this subject.
  • The success rate is high for this subject but only candidates who are civil engineers will have a chance of completing the preparation before the exam since it is a very specialized subject.

Chemical engineering

  • The subject is fairly scoring but cannot be considered highly scoring.
  • There are good and standard books available for this subject in the market but it is rather difficult to get ready made notes and materials.
  • The syllabus is quite lengthy.
  • Coaching is not available for this specific subject but you can get guidance from other qualified candidates who are also chemical engineering graduates.
  • The success rate of the subject is not very high.


  • Forestry is a specialised subject but has ample scope to score well.
  • There is an abundance of materials available as it is a very well-established optional subject for IFoS preparation.
  • The syllabus is short and precise and hence can be quickly completed.
  • Coaching and guidance is available for the subject, though not in abundance.
  • It is considered one of the most successful subjects for IFoS optional.


  • This subject has excellent capacity for fetching marks as it is purely logical- you can be either wrong or right.
  • Maths is a very well established subject which is taught in almost all the universities of the country and hence here are many good materials available for the subject.
  • The syllabus is moderately lengthy.
  • Very good coaching and guidance is available for the subject.
  • Maths is one of the subjects with the highest success rate and hence a number of people opt for it.


  • Candidates who take up geology optional find the subject fairly scoring.
  • Good books on geology are not easily available in the market and though it is an established subject, the materials are difficult to come across.
  • The syllabus is moderately lengthy.
  • There are many candidates who have aced the exam with geology optional and hence guidance is fairly available. However, there are almost no coaching centres.
  • The success rate of the subject is average and usually graduate students of geography who have taken up the subject as optional make it to the final merit list.


  • With no scope for open interpretation of the answers, the subject is very scoring.
  • There are very good materials and books available for the subject given it is widely established and most national universities teach physics.
  • The syllabus is quite lengthy.
  • There is a good amount of coaching as well as guidance available for physics.
  • The success rate of physics is moderately high and many graduates of botany and zoology opt for this subject.

Agricultural engineering

  • The marks fetching ability is fairly good for agricultural engineering.
  • Materials and books are however, not easily available for the subject.
  • The syllabus is moderately lengthy.
  • There is very less coaching and guidance available for the subject.
  • It has an average success rate in the IFoS exams.

Mechanical engineering

  • The marks fetching ability of the subject is quite good.
  • Many national universities teach this subject and hence the materials and books have a good standard and are readily available.
  • The syllabus is moderately lengthy for mechanical engineering.
  • Coaching and guidance is quite available when compared to some other subjects available for optional.
  • The success rate is also fairly high but being a specialized subject, only mechanical engineering graduates usually ace it.


  • The marks fetching capacity is very high in zoology.
  • There are many good books which are readily available for the subject which is taught in almost every college and university in the country.
  • The syllabus of zoology is quite lengthy.
  • Coaching is available easily and so is guidance as there are many IFoS qualified candidates who have zoology in combination, ready to offer their help.
  • This is one of the most scoring subjects and hence the success rate is also very high.


  • Statistics is scoring but the subject is quite challenging.
  • There are many materials available in the market for this subject.
  • The syllabus of statistics is moderately lengthy.
  • There is a fair amount of guidance available.
  • The success rate is average owing to the difficulty level of the subject.

Tips to choose the right Optional Combination

You have to select your optional subjects right at the time of registration. Hence, you must study the pros and cons of the different subjects earlier so that you can make an informed decision. The following are a few generic suggestions which will help you to narrow down the list further-

  • Start shortlisting the subjects by ruling out the ones that have no relevance to your academic background and there is no way of preparing them thoroughly without any specialization. For example, if you are a botany graduate, civil engineering is not an optional that you can grasp in the few months you get for preparation.
  • Consider the available time and whether you can completely utilize it while choosing a subject that you are not very familiar with. Even if a subject is relevant to your academic stream, it is not always likely that you can prepare it completely in a short time span.
  • Try skimming through the syllabus of each subject before filling up the form to determine which the most suitable option is. Remember the combinations that cannot be taken while making the first choice of the subject. Also, choose a subject that you are most comfortable with as the first choice.
  • If you are not in touch with your academic subject for a long time, and not very comfortable either with it, do not choose it as an optional.
  • Do not choose a subject as an optional only because it's syllabus is short and it has a high success rate. Remember that a subject will help you ace the exam, irrespective of its difficulty level only if your preparation is up to the mark.
  • In the worst case scenario where you are not too confident with any of the optional subjects, consider the following factors-
    • Which subject is the most relevant to your academic specialization?
    • Which subject has the smallest and easiest syllabus?
    • Which subject has the maximum scope for scoring?
    • Which of the optional subjects do you feel enthusiastic about studying?
    • Which subjects are overlapping the most with your general studies papers and prelims?
  • Do not take up an optional subject because someone you know aced the exam with it and is available to guide you. Understand whether you have an aptitude for the specific subject and make the choice accordingly.

*The article might have information for the previous academic years, please refer the official website of the exam.