How many contrasting characters were selected by Mendel?

Options

A. One
B. Two
C. Three
D. Seven

Answer

To determine how many contrasting characters were selected by Mendel, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Subject of Mendel's Experiments**: Mendel conducted his experiments primarily on pea plants, specifically the species Pisum sativum.

2. **Understand the Concept of Contrasting Characters**: Contrasting characters refer to pairs of traits that are opposite to each other, such as tall vs. short plants, yellow vs. green seeds, etc.

3. **Count the Pairs of Contrasting Characters**: Mendel selected seven pairs of contrasting characters for his experiments. These pairs included traits like:
- Tall vs. Short
- Yellow vs. Green seeds
- Round vs. Wrinkled seeds
- Purple vs. White flowers
- Inflated vs. Constricted pods
- Yellow vs. Green pods
- Axial vs. Terminal flowers

4. **Conclusion**: Based on the above information, Mendel selected a total of **seven pairs** of contrasting characters for his genetic experiments.

### Final Answer:
Mendel selected **seven contrasting characters**.

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