[A] : Spermatogenesis occurs in the seminiferous tubules of the testes which also produce testosterone in interstitial cells.
[R]: Testosterone maintains the secondary sex characteristics of males, such as low voice, facial hair and increased muscle strength.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

### Step-by-Step Solution:

1. **Understanding the Statements**:
- Statement [A] discusses spermatogenesis occurring in the seminiferous tubules of the testes and mentions that testosterone is produced in the interstitial cells.
- Statement [R] explains the role of testosterone in maintaining secondary sex characteristics in males.

2. **Evaluating Statement [A]**:
- Spermatogenesis is the process of sperm formation.
- This process occurs specifically in the seminiferous tubules located within the testes.
- Interstitial cells (also known as Leydig cells) are responsible for producing testosterone.
- Conclusion: Statement [A] is **true**.

3. **Evaluating Statement [R]**:
- Testosterone is indeed responsible for the development and maintenance of secondary sexual characteristics in males.
- These characteristics include a deeper voice, facial hair, and increased muscle strength.
- Conclusion: Statement [R] is also **true**.

4. **Analyzing the Relationship Between A and R**:
- While both statements are true, we need to determine if [R] provides a correct explanation for [A].
- Statement [A] focuses on the process of spermatogenesis and testosterone production.
- Statement [R] discusses the effects of testosterone but does not explain how it relates to the process of spermatogenesis.
- Conclusion: Statement [R] does not serve as a correct explanation for [A].

5. **Final Answer**:
- Both statements [A] and [R] are true, but [R] is not the correct explanation of [A].