Which of the following is not a helminth ?

Options

A. Trypanosoma
B. Taenia
C. Ascaris
D. Wucheria

Answer

To determine which of the following is not a helminth, we need to understand what helminths are and identify each option provided in the question.

### Step-by-Step Solution:

1. **Definition of Helminths**: Helminths are a group of parasitic worms that include flatworms (like tapeworms) and roundworms. They are multicellular organisms and are typically classified into three main groups: cestodes (tapeworms), trematodes (flukes), and nematodes (roundworms).

2. **Analyze the Options**:
- **Trypanosoma**: This is a protozoan parasite known for causing diseases such as sleeping sickness. Since it is a single-celled organism, it does not belong to the helminth group.
- **Tenia**: This refers to tapeworms, which are flatworms and are classified as helminths. They cause diseases such as Taeniasis.
- **Ascariasis**: This is caused by Ascaris, a type of roundworm (nematode), which is also classified as a helminth.
- **Ucheria**: This refers to Wuchereria, which is a roundworm that causes filariasis (also known as elephantiasis). It is classified as a helminth.

3. **Conclusion**: Among the options, Trypanosoma is the only organism that is not a helminth, as it is a protozoan.

### Final Answer:
The organism that is not a helminth is **Trypanosoma**.