Bulbourethral gland secretes:

Options

A. Mucus into urethra
B. Alkaline fluid into urethra
C. Fluids for semen during ejaculation
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Gland**: The question asks about the Bulbourethral gland, also known as Cowper's gland.

2. **Understand the Function**: The primary function of the Bulbourethral gland is to secrete a fluid that plays a role in the male reproductive system.

3. **Determine the Composition of the Secretion**: The Bulbourethral gland secretes an alkaline fluid, which is primarily composed of mucus. This secretion helps to neutralize the acidity in the urethra and the vagina.

4. **Identify the Purpose of the Secretion**:
- The alkaline mucus neutralizes the acidity of the urethra, which can be harmful to sperm.
- It also neutralizes the acidity of the vagina, providing a more favorable environment for sperm.
- Additionally, this secretion provides lubrication, which is important during sexual intercourse.

5. **Evaluate the Options Given**:
- Option 1: Mucus into urethra - This is correct.
- Option 2: Alkaline fluid into urethra - This is also correct.
- Option 3: Fluid for semen during ejaculation - This is not entirely accurate; while the secretion does mix with semen, it is not specifically for that purpose.
- Option 4: All of these - This is misleading because not all options are correct.

6. **Conclusion**: The most accurate answer based on the functions and characteristics of the Bulbourethral gland is that it secretes alkaline mucus into the urethra.

**Final Answer**: The Bulbourethral gland secretes alkaline mucus into the urethra.

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