Assertion A: The IQ scores of the children of mothers who are exposed to teratogens are found to be low.
Reason R: The use of drugs, alcohol consumption and smoking by mothers lead to central nervous system dysfunction in children.
In the light of the above statements, choose the most appropriate answer from the options given below:
Assertion A states that children born to mothers exposed to teratogens often have low IQ scores. Teratogens are substances or agents that can cause developmental abnormalities in a fetus. Exposure to certain teratogens, particularly during critical periods of brain development, can indeed lead to cognitive impairments, including lower IQ.
Therefore, Assertion A is considered correct.
Reason R explains that the use of drugs, alcohol consumption, and smoking by mothers can lead to central nervous system (CNS) dysfunction in children. These substances are well-documented teratogens. Maternal use of alcohol can cause Fetal Alcohol Spectrum Disorders (FASDs), drug abuse can lead to Neonatal Abstinence Syndrome and developmental issues, and smoking can impair fetal growth and brain development. All these can result in impaired CNS function.
Therefore, Reason R is considered correct.
Reason R provides a direct mechanism explaining Assertion A. Central nervous system dysfunction, caused by maternal exposure to teratogens like drugs, alcohol, and smoking, directly impacts cognitive functions, including intelligence (IQ). A compromised CNS structure or function will likely result in lower cognitive abilities.
Thus, Reason R is the correct explanation of Assertion A.
Both Assertion A and Reason R are correct statements, and Reason R accurately explains why Assertion A is true.