Illicium is modification of :

Options

A. Dorsal fin
B. Caudal fin
C. Scales
D. Ist dorsal spine

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Illicium":**
- Illicium is a specialized structure found in certain fish species, often referred to as a "fishing pole."

2. **Analyzing the Options:**
- The question presents four options to identify what Illicium is a modification of.

3. **Evaluating Each Option:**
- **Option 1: Dorsal Fin**
- The dorsal fin is located on the back of fish and aids in stability and maneuverability. This is not the correct answer.
- **Option 2: Caudal Fin**
- The caudal fin, or tail fin, is located at the end of the fish's body and is primarily used for propulsion. This is also not the correct answer.
- **Option 3: Scales**
- Scales are dermal structures that cover the skin of fish, providing protection. This option is incorrect as well.
- **Option 4: 1st Dorsal Spine**
- The Illicium is indeed a modification of the first dorsal spine in certain fish species, making this the correct answer.

4. **Conclusion:**
- After evaluating all options, it is clear that the Illicium is a modification of the 1st dorsal spine.

**Final Answer:**
- Illicium is a modification of the 1st dorsal spine.

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