Pharyngeal gill-slits are found in

Options

A. Cray fish
B. Cuttle fish
C. Flying fish
D. Silver fish

Answer

**Step-by-Step Solution:**

1. **Understanding Pharyngeal Gill Slits**: Pharyngeal gill slits are anatomical structures that serve as filter-feeding organs in certain organisms. They help in filtering food particles from water.

2. **Identifying the Phylum**: Pharyngeal gill slits are characteristic features of organisms in the phylum Chordata. They are not found in invertebrates, which belong to other phyla.

3. **Analyzing the Options**:
- **Crayfish**: This organism belongs to the phylum Crustacea, which is an invertebrate group. Therefore, it does not have pharyngeal gill slits.
- **Cuttlefish**: Cuttlefish are part of the phylum Mollusca, another invertebrate group. They also do not possess pharyngeal gill slits.
- **Flying Fish (Exocoetus)**: This fish is a member of the phylum Chordata, which means it does have pharyngeal gill slits.
- **Silver Fish**: Silver fish belong to the phylum Arthropoda, which is also an invertebrate group. They do not have pharyngeal gill slits.

4. **Conclusion**: Among the options provided, the only organism that possesses pharyngeal gill slits is the flying fish (Exocoetus), as it is a member of the phylum Chordata.

**Final Answer**: Pharyngeal gill slits are found in flying fish (Exocoetus).

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