Which of the following statement is correct?

Options

A. Ovules are not enclosed by ovary wall in gymnosperum
B. Selaginella is heterosporous, while Salvieeis homosporous
C. Horsetails are gymnosperms
D. Stems are usually unbranched in both Cycas

Answer

To determine which of the statements is correct, we will analyze each statement one by one based on our knowledge of plant biology, particularly focusing on Gymnosperms and Pteridophytes.

### Step-by-Step Solution:

1. **Analyze Statement 1**: "Ovules are not enclosed by ovary wall in Gymnosperm."
- **Explanation**: Gymnosperms are known for having seeds that are not enclosed in an ovary wall. The term "Gymnosperm" itself means "naked seeds". This statement is correct.

2. **Analyze Statement 2**: "Slaginella as Heterosporous, while Salvinia as Homosporous."
- **Explanation**: Both Selaginella and Salvinia are actually heterosporous plants. Heterosporous plants produce two types of spores: microspores and megaspores. This statement is incorrect.

3. **Analyze Statement 3**: "Horse tails are gymnosperms."
- **Explanation**: Horse tails belong to the group of Pteridophytes, specifically the class Equisetopsida. They are not gymnosperms. This statement is incorrect.

4. **Analyze Statement 4**: "Stems are usually branched in both Cycas and Pinus."
- **Explanation**: Cycas (a type of cycad) typically has unbranched stems, while Pinus (a type of conifer) has branched stems. Therefore, this statement is also incorrect.

### Conclusion:
After analyzing all four statements, the only correct statement is the first one: "Ovules are not enclosed by ovary wall in Gymnosperm."

### Final Answer:
The correct statement is: **1. Ovules are not enclosed by ovary wall in Gymnosperm.**

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