Sponges are

Options

A. unisexual
B. Sexually sterile
C. hermaphrodies
D. sexually dimorphic

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the reproductive nature of sponges. We need to identify which of the given options correctly describes sponges.

2. **Evaluating Option A - Unisexual**:
- Unisexual organisms produce gametes from two different individuals (male and female).
- Sponges do not fit this description as they can produce both types of gametes from a single individual.
- **Conclusion**: Sponges are not unisexual.

3. **Evaluating Option B - Sexually Sterile**:
- Sexually sterile organisms cannot produce any gametes (neither sperm nor ovum).
- Sponges are capable of producing gametes, so they do not fall under this category.
- **Conclusion**: Sponges are not sexually sterile.

4. **Evaluating Option C - Hermaphrodite**:
- Hermaphrodite organisms can produce both male and female gametes.
- Sponges are indeed hermaphroditic as they can produce both sperm and ovum from the same individual.
- **Conclusion**: This option is correct; sponges are hermaphrodite.

5. **Evaluating Option D - Sexually Diamorphic**:
- Sexual diamorphism refers to systematic differences between the sexes of the same species.
- Sponges do not exhibit such differences as they can produce both gametes from the same individual.
- **Conclusion**: Sponges are not sexually diamorphic.

6. **Final Answer**: Based on the evaluations, the correct answer is that sponges are hermaphrodite.

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