In B-DNA each helical turn contains

Options

A. 12 base pairs
B. 10 base pairs
C. 8 base pairs
D. 11 base pairs

Answer

To solve the question regarding how many base pairs are contained in each helical turn of B-DNA, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of B-DNA**:
- B-DNA is one of the most common forms of DNA in cells. It is a double helix structure where two strands of DNA wind around each other.

2. **Identify the Options**:
- The question provides four options: 12 base pairs, 10 base pairs, 8 base pairs, and 11 base pairs.

3. **Refer to Known Data**:
- It is essential to know the characteristics of different DNA forms. For B-DNA, it is well-documented that each complete helical turn contains a specific number of base pairs.

4. **Recall the Number of Base Pairs in B-DNA**:
- Research and biological literature indicate that B-DNA has approximately 10 base pairs per helical turn.

5. **Select the Correct Answer**:
- Based on the information gathered, the correct answer to the question is that B-DNA contains **10 base pairs** in each helical turn.

### Final Answer:
- **10 base pairs**.