Nephridia as excretory organ are found in ________

Options

A. platyhelminthes
B. annelida
C. arthropoda
D. porifera

Answer

To answer the question "Nephridia as excretory organ are found in ________", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the term 'Nephridia':**
- Nephridia are tubular structures that function as excretory organs in certain invertebrates. They help in the removal of waste products from the body.

2. **Identify the options provided:**
- The question typically provides multiple-choice options. In this case, we will consider the common groups of animals that might be listed, such as Platyhelminthes, Annelida, Arthropoda, and Porifera.

3. **Analyze each option:**
- **Platyhelminthes:**
- The excretory system in Platyhelminthes consists of flame cells (or protonephridia), not nephridia. Therefore, this option is incorrect.
- **Annelida:**
- Annelids, such as earthworms, possess nephridia as their excretory organs. They are responsible for the excretion of waste materials. This option is correct.
- **Arthropoda:**
- In Arthropods, the excretory organs include Malpighian tubules, antennal glands, or maxillary glands, but not nephridia. Thus, this option is incorrect.
- **Porifera:**
- Porifera (sponges) do not have a distinct excretory system; they rely on the flow of water through their bodies to expel waste. Therefore, this option is also incorrect.

4. **Conclude the answer:**
- Based on the analysis, the correct answer is **Annelida**, as they are the group of animals that possess nephridia as their excretory organ.

### Final Answer:
Nephridia as excretory organ are found in **Annelida**.

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