Which of the following groups is formed only of the hermaphrodite organisms ?

Options

A. Earthworm, tapeworm, housefly, frog
B. Earthworm, tapeworm, sea horse, housefly
C. Earthworm, leech, sponge, roundworm
D. Earthworm, tapeworm, leech, sponge

Explanation

To determine which group is formed only of hermaphrodite organisms, we need to identify the reproductive characteristics of the organisms in each option provided.

### Step-by-Step Solution:

1. **Define Hermaphrodite Organisms**:
Hermaphrodite organisms are those that possess both male and female reproductive organs within the same individual. They are also referred to as bisexual or monoecious.

2. **Analyze Each Option**:
We will evaluate the organisms in each option to see if they are hermaphrodites.

- **Option A**:
- Earthworm: Hermaphrodite (bisexual)
- Tapeworm: Hermaphrodite (bisexual)
- Housefly: Unisexual (dioecious)
- Frog: Unisexual (dioecious)
- **Conclusion**: This option is incorrect as it contains unisexual organisms.

- **Option B**:
- Earthworm: Hermaphrodite (bisexual)
- Tapeworm: Hermaphrodite (bisexual)
- Seahorse: Unisexual (dioecious)
- Housefly: Unisexual (dioecious)
- **Conclusion**: This option is incorrect as it contains unisexual organisms.

- **Option C**:
- Earthworm: Hermaphrodite (bisexual)
- Leech: Hermaphrodite (bisexual)
- Sponges: Hermaphrodite (bisexual)
- Roundworm: Unisexual (dioecious)
- **Conclusion**: This option is incorrect as it contains unisexual organisms.

- **Option D**:
- Earthworm: Hermaphrodite (bisexual)
- Tapeworm: Hermaphrodite (bisexual)
- Leech: Hermaphrodite (bisexual)
- Sponge: Hermaphrodite (bisexual)
- **Conclusion**: This option is correct as all listed organisms are hermaphrodites.

3. **Final Answer**:
The group that is formed only of hermaphrodite organisms is **Option D**.