Mendel selected _____ true-breeding pea plant varieties as pairs for his experiments.

Options

A. 7
B. 14
C. 2
D. 1

Answer

To answer the question about how many true-breeding pea plant varieties Mendel selected for his experiments, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Subject**: Understand that the question is about Gregor Mendel and his experiments with pea plants.

2. **Recall Mendel's Experiments**: Mendel conducted hybridization experiments on garden peas from 1856 to 1863. He is known for his foundational work in genetics.

3. **Determine the Number of Varieties**: Mendel selected true-breeding varieties of pea plants for his experiments. The key detail is the number of these varieties.

4. **Review the Options**: The options provided are 7, 14, 2, and 1.

5. **Identify the Correct Answer**: It is known from Mendel's work that he selected **14 true-breeding pea plant varieties** for his experiments.

6. **Conclude**: Therefore, the answer to the question is 14.

### Final Answer:
Mendel selected **14** true-breeding pea plant varieties as pairs for his experiments.

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