A cross involving two pairs of alleles is

Options

A. Crossing over
B. Genetics
C. Dihybrid cross
D. Monohybrid cross.

Answer

To solve the question about a cross involving two pairs of alleles, we will analyze the definitions and characteristics of the different types of genetic crosses mentioned in the options.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Monohybrid Cross**: This involves a cross between two organisms that differ in only one trait. For example, crossing a tall plant with a short plant to study the inheritance of height.
- **Dihybrid Cross**: This involves a cross between two organisms that differ in two traits. For example, crossing a plant with red flowers and tall height with a plant with white flowers and dwarf height. This cross studies the inheritance of both flower color and plant height.
- **Crossing Over**: This is a process that occurs during meiosis where segments of chromatids are exchanged between non-sister chromatids. It is not a type of genetic cross.

2. **Identifying the Correct Cross**:
- The question specifies a cross involving **two pairs of alleles**. This indicates that two traits are being studied simultaneously.
- Since we are looking at two traits, the appropriate type of cross is a **dihybrid cross**.

3. **Eliminating Incorrect Options**:
- **Crossing Over**: This is not a type of genetic cross but rather a genetic process, so it is incorrect.
- **Monohybrid Cross**: This only involves one trait, which does not fit the requirement of the question.
- **Genetics**: This is a broad field of study and not a specific type of cross.

4. **Conclusion**:
- Based on the analysis, the correct answer to the question about a cross involving two pairs of alleles is a **dihybrid cross**.

### Final Answer:
The correct answer is **Dihybrid Cross**.

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