Which of the following structure helps in excretion and respiration in molluscs?

Options

A. Nephridia
B. Feather-like gills
C. Flame cells
D. Tentacles

Explanation

To answer the question regarding which structure helps in excretion and respiration in molluscs, we can follow these steps:

### Step 1: Understand the Structures Listed
The question provides four options:
1. Nephridia
2. Feather-like gills
3. Flame cell
4. Tentacles

### Step 2: Analyze Each Structure
- **Nephridia**: This structure is primarily associated with the excretory system in annelids (like earthworms) and is not a characteristic of molluscs.

- **Feather-like gills**: These are typically found in aquatic animals for respiration, but they are not the primary structures for excretion in molluscs.

- **Flame cell**: This structure is involved in excretion and is found in some invertebrates, but it is not the primary excretory structure in molluscs.

- **Tentacles**: These structures are primarily used for locomotion and sensory functions in various invertebrates, including cnidarians, but they do not play a role in excretion or respiration in molluscs.

### Step 3: Identify the Correct Structure for Molluscs
In molluscs, the primary structures involved in excretion and respiration are:
- **Nephridia**: While not exclusive to molluscs, they do have a similar function in excretion.
- **Gills**: Molluscs, especially aquatic ones, have gills for respiration.

### Conclusion
The most appropriate answer to the question is **feather-like gills** for respiration, while nephridia can be associated with excretion.

### Final Answer
**Feather-like gills** help in respiration in molluscs, while **nephridia** are involved in excretion.

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