Among the following organisms point out a completely non-parasitic form

Options

A. Tape worm
B. Mosquito
C. Sea anemone
D. Leech

Explanation

To determine which of the given organisms is completely non-parasitic, we will analyze each option one by one:

1. **Tapeworm**:
- Tapeworms are known to be endoparasites, meaning they live inside the host's body and derive nutrients at the host's expense. Therefore, tapeworms are parasitic.
- **Conclusion**: This option is incorrect.

2. **Mosquito**:
- Mosquitoes are ectoparasites as they feed on the blood of their hosts (such as humans and animals) by biting them. This feeding behavior classifies them as parasitic.
- **Conclusion**: This option is also incorrect.

3. **Sea Anemone**:
- Sea anemones are known to engage in mutualistic relationships, particularly with hermit crabs. In this relationship, both organisms benefit from each other, which means that sea anemones do not harm their partners and are not parasites.
- **Conclusion**: This option is correct as it represents a completely non-parasitic form.

4. **Leech**:
- Leeches are also ectoparasites, feeding on the blood of other organisms. They attach to their hosts and draw blood, which makes them parasitic.
- **Conclusion**: This option is incorrect.

**Final Answer**: The completely non-parasitic form among the given options is **Sea Anemone** (Option 3).