Indusium occurs in

Options

A. Algae
B. Fronds
C. Moss
D. Cycas

Answer

**Step-by-Step Solution:**

1. **Understanding Indusium:** Indusium is defined as a membranous covering that is found in certain plants. It serves a protective function.

2. **Identifying the Context:** The question asks where indusium occurs. We need to look at the options provided: algae, fronds, moss, and cycads.

3. **Analyzing the Options:**
- **Algae:** These are simple aquatic organisms and do not have indusium.
- **Fronds:** These are the leaves of ferns, and indusium is known to occur in some types of fern fronds.
- **Moss:** Mosses are non-vascular plants and do not have indusium.
- **Cycads:** These are seed plants and do not possess indusium.

4. **Conclusion:** Since indusium is specifically found in some fern fronds, the correct answer is option number two: **fronds**.

**Final Answer:** Indusium occurs in **fronds**.

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