Reproduction in ctenophores takes place by

Options

A. only asexual
B. only budding
C. only fragmentation
D. only sexual

Answer

### Step-by-Step Solution:

1. **Understanding Ctenophores**: Ctenophores are a group of marine invertebrates known for their unique body structure and locomotion using cilia. They are also known as "comb jellies."

2. **Reproductive Organs**: Ctenophores possess both male and female reproductive organs. This means they have the capability to produce both sperm and eggs.

3. **Mode of Reproduction**: The primary mode of reproduction in ctenophores is sexual reproduction. This involves the mating of male and female ctenophores.

4. **Process of Reproduction**:
- During mating, ctenophores release their sex cells (sperm and eggs) into the water.
- This process occurs through their mouth, which is a unique characteristic of their reproductive behavior.
- The released sex cells then undergo fertilization in the water.

5. **Development**: After fertilization, the fertilized eggs develop into larvae, which eventually mature into adult ctenophores.

6. **Conclusion**: Therefore, the reproduction in ctenophores takes place primarily through sexual means, involving both internal and external processes.

### Final Answer:
Reproduction in ctenophores takes place by sexual means.

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