A grass which has both `C_(3)` and `C_(4)` ecotypes is

Options

A. Alloteropsis semi-alata
B. Imperata cylindrica
C. Cynodon dactylon
D. Agropyron repens.

Answer

To determine which grass has both C3 and C4 ecotypes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- C3 and C4 refer to different pathways of photosynthesis. C3 plants primarily use the Calvin cycle, while C4 plants have an additional step that allows them to efficiently fix carbon dioxide in high light and temperature conditions.

2. **Analyze the Options**:
- We have four options:
- A) Allotropis Semialata
- B) Imperata cylindrica
- C) Cynodon dactylon
- D) Agropyron repens

3. **Research Each Option**:
- **Allotropis Semialata** (Black Seed Grass): This grass can grow in both tropical and temperate areas. In tropical areas, it can utilize the C4 pathway, while in temperate areas, it can utilize the C3 pathway.
- **Imperata cylindrica** (Kundia Grass): This grass primarily follows the C4 photosynthetic pathway.
- **Cynodon dactylon** (Bermuda Grass): This grass also primarily follows the C4 pathway.
- **Agropyron repens**: This grass is known to follow the C4 pathway as well.

4. **Identify the Correct Answer**:
- Since we are looking for a grass that has both C3 and C4 ecotypes, the only option that fits this criterion is **Allotropis Semialata**.

5. **Conclusion**:
- The grass that has both C3 and C4 ecotypes is **Allotropis Semialata** (Option A).

### Final Answer:
The correct answer is **A) Allotropis Semialata**.

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