Analyzing Ranking Sufficiency

The question asks to identify who ranked first in the class. We need to determine if the given statements are sufficient to answer this.

Statement Analysis

• Statement I: Sreeja ranked $2^{\text{nd}}$. This statement alone does not tell us who is first.
• Statement II: Aman ranked one rank below Sreeja. If Sreeja is $2^{\text{nd}}$, Aman is $3^{\text{rd}}$. This statement alone does not reveal the first rank.
• Statement III: Rohit ranked better than Aman. This means Rohit's rank is less than Aman's. Without knowing Aman's specific rank, this statement alone is insufficient.

Combined Statement Analysis

Let's analyze the statements together:

• Statements I and II: Sreeja is $2^{\text{nd}}$ and Aman is $3^{\text{rd}}$. This leaves the $1^{\text{st}}$ rank unknown. Not sufficient.
• Statements I and III: Sreeja is $2^{\text{nd}}$. Rohit ranked better than Aman. We don't know Aman's rank, so this combination is insufficient.
• Statements II and III: Aman's rank = Sreeja's rank + 1. Rohit's rank < Aman's rank. This only gives a relative order (Rohit < Aman < Sreeja) but not the exact ranks or who is first. Not sufficient.
• Statements I, II, and III:
  • From I, Sreeja is $2^{\text{nd}}$.
  • From II, Aman is $3^{\text{rd}}$ (one rank below Sreeja).
  • From III, Rohit ranked better than Aman ($3^{\text{rd}}$). This means Rohit could be $1^{\text{st}}$ or $2^{\text{nd}}$.
  • Since Sreeja is already $2^{\text{nd}}$, Rohit cannot be $2^{\text{nd}}$.
  • Therefore, Rohit must be $1^{\text{st}}$.

All three statements together are sufficient to determine that Rohit ranked first.