Sepia and octopus are marine animals and their shiwt locomotion in water is effect by

Options

A. Adhering with the help of suckers to another moving animals
B. Characterstics undulation of their lateral fins
C. Lashing movement of their cephalic arms
D. Expelling water in a jet through siphon.

Answer

**Step-by-Step Solution:**

1. **Identify the Animals**: Recognize that Sepia (cuttlefish) and octopus are marine animals belonging to the phylum Mollusca and class Cephalopoda.

2. **Understand Locomotion**: Both Sepia and octopus utilize a unique form of locomotion in water that is primarily based on expelling water.

3. **Analyze the Options**:
- **Option A**: Adhering with the help of suckers to another moving animal - This is incorrect as it does not describe their primary mode of locomotion.
- **Option B**: Characteristics undulation of their lateral fins - This is also incorrect because cephalopods like octopus and cuttlefish do not have prominent lateral fins.
- **Option C**: Lashing movement of their cephalic arms - While they do use their arms for movement, this is not the primary mechanism for propulsion.
- **Option D**: Expelling water in a jet through siphon - This is the correct answer as it describes the primary method of locomotion for both animals.

4. **Conclusion**: The correct answer is **Option D: Expelling water in a jet through siphon**.

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