The common bread wheat has chromosomes

Options

A. 14
B. 21
C. 28
D. 42

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the number of chromosomes in common bread wheat.

2. **Identifying the Nature of Wheat**: Common bread wheat is known to be hexaploid. This means that it has six sets of chromosomes.

3. **Determining the Number of Chromosomes per Set**: Each set of chromosomes in common bread wheat contains 7 chromosomes.

4. **Calculating the Total Number of Chromosomes**: To find the total number of chromosomes, multiply the number of sets by the number of chromosomes in each set:
\[ \text{Total Chromosomes} = \text{Number of Sets} \times \text{Chromosomes per Set} = 6 \times 7 = 42 \]

5. **Evaluating the Options**: The options provided are 14, 21, 28, and 42. Based on our calculation, the correct answer is 42.

6. **Conclusion**: Therefore, the common bread wheat has a total of 42 chromosomes.

### Final Answer:
The common bread wheat has **42 chromosomes**.

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