Urethral meatus refers to the

Options

A. urinogenital duct.
B. opening of vas deferens into urethra.
C. external opening of the urinogenital duct.
D. muscles surrounding the urinogenital duct.

Explanation

**Step-by-Step Solution:**

1. **Understanding Urethral Meatus**: The urethral meatus is an anatomical term that refers to the external opening of the urethra. It is the point where urine exits the body from the urinary tract.

2. **Identifying the Options**: The question provides four options regarding what the urethral meatus refers to:
- A) Urinogenital duct
- B) Opening of vas deferens into urethra
- C) External opening of urinogenital duct
- D) Muscles surrounding the urinogenital duct

3. **Analyzing Each Option**:
- **Option A (Urinogenital duct)**: This duct connects the urinary and reproductive systems. However, it is not specifically the urethral meatus itself, so this option is incorrect.
- **Option B (Opening of vas deferens into urethra)**: The vas deferens is part of the male reproductive system and connects to the urethra, but this opening is not referred to as the urethral meatus. Therefore, this option is also incorrect.
- **Option C (External opening of urinogenital duct)**: This option accurately describes the urethral meatus, as it is the external opening of the urethra, which can be considered part of the urinogenital duct in males. This is the correct answer.
- **Option D (Muscles surrounding urinogenital duct)**: This refers to the muscles that support the duct but does not define the urethral meatus itself. Thus, this option is incorrect.

4. **Conclusion**: After analyzing all options, the correct answer is **Option C: External opening of urinogenital duct**.

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