What is the most important change marked by puberty?

Explanation

### Step-by-Step Solution:

1. **Understanding Puberty**: Puberty is a transitional phase that marks the change from childhood to adulthood. It typically occurs between the ages of 10 to 13 years.

2. **Changes in Males**:
- One of the most significant changes in males during puberty is the enlargement of the penis.
- Additionally, sperm formation begins, indicating that the male is becoming reproductively capable.

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