Assertion (A) Evaluation

The assertion states that puberty begins earlier in females than in males, and both sexes reach their final height by age 18-20. This is biologically accurate. Females generally enter puberty sooner (around ages 8-13) compared to males (around ages 9-14). Growth typically ceases in the late teens for both, leading to their final adult height within the specified age range.

Therefore, Assertion (A) is true.

Reason (R) Evaluation

The reason claims that although puberty starts later in males, their growth spurt is more rapid than in females. This is also a known physiological fact. Males experience a more pronounced and faster increase in height and weight during their pubertal growth spurt compared to the spurt experienced by females.

Therefore, Reason (R) is true.

Relationship Between Assertion (A) and Reason (R)

While both Statement (A) and Statement (R) are factually correct regarding the timing of puberty, the rate of growth spurts, and final height attainment in females and males, Reason (R) does not serve as a correct explanation for Assertion (A).

• Assertion (A) focuses on the timing difference in puberty onset and the age range for final height.
• Reason (R) describes the later onset in males and the rapidity of their growth spurt.

The fact that males have a more rapid growth spurt does not directly explain why females start puberty earlier or why both reach their final height around the same age. These are related but distinct aspects of adolescent development.

Conclusion: Both (A) and (R) are true, but (R) is not the correct explanation of (A).