Which of these is a primary sexual characteristic in human males?

Options

A. Development of facial hair
B. Presence of a penis
C. Development of mammary glands
D. Broadening of shoulders

Answer

To determine which of the given options is a primary sexual characteristic in human males, we need to understand the distinction between primary and secondary sexual characteristics.

### Step-by-Step Solution:

1. **Define Primary Sexual Characteristics**:
- Primary sexual characteristics are those that are present at birth and are directly related to the reproductive system. In males, these include the penis and testis.

2. **Identify the Options**:
- The options provided are:
A. Development of facial hair
B. Presence of penis
C. Development of mammary glands
D. Broadening of shoulders

3. **Analyze Each Option**:
- **Option A: Development of facial hair**: This is a secondary sexual characteristic that develops during adolescence due to hormonal changes.
- **Option B: Presence of penis**: This is a primary sexual characteristic as it is present at birth and is essential for reproduction.
- **Option C: Development of mammary glands**: This is primarily a characteristic of females and does not develop significantly in males.
- **Option D: Broadening of shoulders**: This is also a secondary sexual characteristic that occurs during adolescence due to hormonal changes.

4. **Conclusion**:
- The correct answer is **Option B: Presence of penis**, as it is the only option that qualifies as a primary sexual characteristic in human males.