Assertion: Infection of the urethra is more common in males than in the females.
Reason: Urethra is shorter in the males than in the females.

Options

A. (a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. (b) If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. (c) If Assertion is true but the Reason is false.
D. (d) If both Assertion and Reason are false.

Answer

To solve the assertion-reason question, we will analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Infection of the urethra is more common in males than in females."
- This statement is **false**. In reality, urinary tract infections (UTIs) are more common in females than in males due to anatomical differences.

2. **Understanding the Reason**: The reason given is "Urethra is shorter in males than in females."
- This statement is also **false**. In fact, the urethra is shorter in females than in males. The female urethra is approximately 4 cm long, while the male urethra is about 20 cm long.

3. **Connecting the Assertion and Reason**: Since both the assertion and the reason are false, we need to determine the relationship between them. The reason does not support the assertion because the length of the urethra is the opposite of what is stated.

4. **Conclusion**: Since both the assertion and the reason are false, the correct option is that both are false.

### Final Answer:
Both the assertion and the reason are false.