Assertion (A): The region outside the seminiferous tubules is called interstitial spaces, which contain Leydig's cells.
Reason (R) : Leydig's cells synthesize and secrete testicular hormones called androgen.

Options

A. Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion(A).
B. Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
C. Assertion (A) is true but reason (R) is false.
D. Assertion (A) is false but reason (R) is true.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the region outside the seminiferous tubules is called interstitial spaces, which contain Leydig's cells.
- This is true because Leydig's cells, also known as interstitial cells, are located in the interstitial spaces between the seminiferous tubules in the testes.

2. **Understanding the Reason (R)**:
- The reason states that Leydig's cells synthesize and secrete testicular hormones called androgens.
- This is also true as Leydig's cells are responsible for producing testosterone, which is a primary androgen involved in male reproductive functions.

3. **Analyzing the Relationship**:
- The assertion correctly identifies the location and function of Leydig's cells, while the reason explains their role in hormone production.
- Therefore, the reason provides a correct explanation for the assertion.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both A and R are true, and R is the correct explanation of A.

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