Devil's Fish expels an ink for

Options

A. Paralysing prey
B. Camouflage
C. Insensitising smelling power of predator
D. Both B and C.

Answer

### Step-by-Step Solution:

1. **Identify the Subject**: The question pertains to the behavior of the Devil's Fish, also known as the Giant Devil Ray (scientific name: Mobula mobula).

2. **Understand the Function of Ink Expulsion**: The Devil's Fish expels ink as a defensive mechanism. This is a common behavior in several marine species to evade predators.

3. **Analyze the Options**:
- **Option A**: Paralyzing prey - This is incorrect as the ink does not paralyze prey.
- **Option B**: Camouflage - This is correct. The ink helps the Devil's Fish to blend into its surroundings, making it harder for predators to spot it.
- **Option C**: Insensitizing the smelling power of the predator - This is also correct. The ink can disrupt the predator's ability to smell, further aiding in the fish's escape.

4. **Determine the Correct Answer**: Since both options B (camouflage) and C (insensitizing the smelling power of the predator) are correct, the best answer is option D (both B and C).

5. **Conclusion**: The Devil's Fish uses ink expulsion primarily for camouflage and to insensitize the predator's sense of smell, thus enhancing its survival chances.

### Final Answer:
The correct option is **D: Both B and C**.

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