Environmental mechanism of sex-determination is seen in

Options

A. Bonnelia
B. Crepidula
C. Grasshopper
D. More than one option is correct

Answer

**Step-by-Step Solution:**

1. **Understanding Environmental Mechanism of Sex Determination (ESD):**
- Environmental mechanism of sex determination refers to the phenomenon where the sex of an organism is determined by environmental factors rather than strictly genetic ones.

2. **Analyzing the Options:**
- The question provides several organisms: Borneania, Cribrula, and Grasshopper. We need to evaluate each one to see if they exhibit ESD.

3. **Borneania:**
- Borneania is a larval organism that can develop into either male or female based on environmental conditions. This indicates that it does exhibit environmental sex determination. Therefore, this option is correct.

4. **Crepidula:**
- Crepidula, a type of snail, also shows environmental sex determination. The sex of Crepidula can change based on its environmental context, such as population density or the presence of other males or females. Thus, this option is also correct.

5. **Grasshopper:**
- Grasshoppers have a fixed genetic mechanism for sex determination, typically following the XX/XY system (where XX is female and XY is male). There is no evidence of environmental influence on their sex determination. Therefore, this option is incorrect.

6. **Conclusion:**
- Since both Borneania and Crepidula exhibit environmental mechanisms of sex determination, while Grasshopper does not, the correct answer is that more than one option is correct.

**Final Answer:**
The environmental mechanism of sex determination is seen in Borneania and Crepidula.

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