When two unrelated individuals or lines are crossed, the perfomance of `"F"_(1)` hybrid is often superior to both its parents. This phenomenon is called:

Options

A. Heterosis
B. Transformation
C. Splicing
D. Metamorphosis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the phenomenon where the performance of the F1 hybrid (the first generation offspring from two different parental lines) is superior to both of its parents when they are crossed.

2. **Identifying Key Terms**: The key terms in the question are "F1 hybrid," "superior performance," and "crossed." This indicates that we are looking for a specific biological phenomenon related to hybridization.

3. **Exploring the Options**: The options provided are:
- A) Heterosis
- B) Transformation
- C) Splicing
- D) Metamorphosis

4. **Analyzing Each Option**:
- **A) Heterosis**: This term refers to the phenomenon where hybrids exhibit greater vigor, growth, or yield compared to their parents. This is the correct answer.
- **B) Transformation**: This refers to the genetic alteration of a cell due to the uptake of external genetic material. It does not relate to hybrid vigor.
- **C) Splicing**: This is a molecular biology process where introns are removed and exons are joined together in RNA processing. It is unrelated to hybrid performance.
- **D) Metamorphosis**: This is a biological process involving significant physical changes in an organism after birth, such as in insects. It does not pertain to hybrid vigor.

5. **Conclusion**: Based on the analysis, the correct answer to the question is **A) Heterosis**. This phenomenon explains why the F1 hybrid can outperform its parents.

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