Mendel was the first scientist to study the pattern of inheritance. He is known as the father of genetics and proposed the laws of inheritance. He selected pea plants (Pisum sativum) to carry out his study on the inheritance of characters from parents to offspring. Mendel carried the process of self-pollination followed by cross-pollination in his experiment.
A cross between two plants, which differs in only one pair of contrasting characters is called _______

Options

A. monohybrid cross
B. dihybrid cross
C. cross-pollination
D. self-pollination

Answer

To answer the question, we need to identify the type of cross Mendel performed when he studied the inheritance of a single pair of contrasting characters.

### Step-by-Step Solution:

1. **Understanding the Types of Crosses**:
- Mendel's experiments involved different types of crosses. The two main types are:
- **Monohybrid Cross**: This involves a cross between two plants that differ in only one trait (or character).
- **Dihybrid Cross**: This involves a cross between two plants that differ in two traits.

2. **Identifying the Correct Cross**:
- The question specifies that the cross is between two plants that differ in only one pair of contrasting characters. This directly matches the definition of a monohybrid cross.

3. **Conclusion**:
- Therefore, the answer to the question is that a cross between two plants which differs in only one pair of contrasting characters is called a **monohybrid cross**.

### Final Answer:
A cross between two plants, which differs in only one pair of contrasting characters is called **monohybrid cross**.

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