`HSK` pathway is also known as

Options

A. `C_(3)` cycle
B. `C_(4)` cycle
C. `C_(2)` cycle
D. None of the above.

Answer

### Step-by-Step Solution:

1. **Identify the HSK Pathway**: The HSK pathway refers to a specific metabolic pathway involved in photosynthesis.

2. **Understand the Context**: The HSK pathway is associated with the dark reactions of photosynthesis, specifically in plants that utilize the C4 pathway.

3. **Differentiate Between Pathways**: There are two main types of pathways in the dark reaction of photosynthesis:
- The C3 pathway, also known as the Calvin cycle, discovered by Melvin Calvin.
- The C4 pathway, which is where the HSK pathway comes into play.

4. **Name the Scientists**: The C4 pathway is also referred to as the Hatch and Slack pathway, named after the scientists who discovered it.

5. **Conclusion**: Therefore, the HSK pathway is also known as the C4 cycle or the Hatch and Slack pathway.

### Final Answer:
The HSK pathway is also known as the **Hatch and Slack pathway** or the **C4 cycle**.

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