A pleiotropic in Drosophila is that of

Options

A. Red-white eye
B. Bar eye
C. Vestigial gene
D. Forked bristles.

Answer

To solve the question regarding a pleiotropic gene in Drosophila, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Pleiotropy**:
- Pleiotropy refers to a situation where a single gene influences multiple phenotypic traits. This means that one gene can affect more than one characteristic in an organism.

2. **Identifying the Options**:
- The options provided are:
- a) Red
- b) White
- c) I-bar
- d) Vestigial gene
- e) Fog bristles

3. **Analyzing Each Option**:
- **Red and White**: These are typically associated with eye color in Drosophila, but they do not exhibit pleiotropy as they are primarily linked to a single trait.
- **I-bar**: This is a genetic mutation that affects the shape of the eye but does not show pleiotropic effects on multiple traits.
- **Vestigial Gene**: This gene is known to have pleiotropic effects. It affects the wing shape and can also influence other traits such as body size and fertility.
- **Fog Bristles**: This gene is associated with bristle morphology but does not exhibit multiple trait influence.

4. **Conclusion**:
- Based on the analysis, the vestigial gene is the best example of a pleiotropic gene in Drosophila as it affects multiple traits.

5. **Final Answer**:
- The correct answer is **d) Vestigial gene**.