How many teeth in man grows twice in life

Options

A. 32
B. 28
C. 20
D. 12

Answer

To solve the question "How many teeth in man grow twice in life?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Teeth**: Humans have two types of teeth during their lifetime: temporary (also known as deciduous or milk teeth) and permanent teeth.

2. **Identify Temporary Teeth**: Temporary teeth are the first set of teeth that appear in children. These include incisors, canines, and molars.

3. **Count the Number of Temporary Teeth**: In total, there are 20 temporary teeth in humans. This includes:
- 8 incisors (4 on the top and 4 on the bottom)
- 4 canines (2 on the top and 2 on the bottom)
- 8 molars (4 on the top and 4 on the bottom)

4. **Understand the Growth Process**: These 20 temporary teeth grow in early childhood and are eventually replaced by permanent teeth as the child grows.

5. **Conclusion**: Since these temporary teeth are replaced once, we can conclude that they "grow twice" in life: once as temporary teeth and once as permanent teeth.

6. **Final Answer**: Therefore, the number of teeth in man that grow twice in life is **20**.