The larva of Sycon is

Options

A. Parenchymula
B. redia
C. Planula
D. amphiblastula

Answer

To solve the question "The larva of Sycon is," we will analyze each option provided and identify the correct answer based on our knowledge of larval forms in different organisms.

### Step-by-step Solution:

1. **Understand the Organism**:
- Sycon is a genus of sponges, which belong to the phylum Porifera.

2. **Analyze the Options**:
- **Option 1: Parenchymula**
- This is known to be the larval form of certain sponges, specifically Deucoselenia.
- **Option 2: Radia**
- The Radia larva is associated with liver flukes, which are flatworms, not sponges.
- **Option 3: Planula**
- The Planula larva is typically found in cnidarians (like jellyfish) and some ctenophores, not in sponges.
- **Option 4: Amphiblastula**
- The Amphiblastula is recognized as the larval form of Sycon, which is a sponge.

3. **Identify the Correct Answer**:
- Since we have established that Sycon is a sponge and the larval form associated with it is the Amphiblastula, we can conclude that the correct answer is **Amphiblastula**.

### Final Answer:
The larva of Sycon is **Amphiblastula**.

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