Who described `C_(4)` pathway for the first time ?

Options

A. Hatch and Slack
B. Robert hill
C. Calvin
D. Watson and Crick

Answer

To answer the question "Who described the C4 pathway for the first time?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the C4 Pathway**:
- The C4 pathway is a type of photosynthetic process that some plants use to fix carbon dioxide. It is different from the C3 pathway, which is the more common form of photosynthesis.

2. **Identifying Key Scientists**:
- The question provides multiple-choice options, likely including names of various scientists. We need to focus on those who have made significant contributions to the understanding of photosynthesis.

3. **Reviewing Contributions**:
- Calvin is known for the Calvin cycle, which is related to the C3 pathway.
- Robert Hill is known for the Hill reaction, which is also not related to the C4 pathway.
- Watson and Crick are famous for their discovery of the structure of DNA, which is unrelated to photosynthesis.

4. **Identifying the Correct Scientists for C4 Pathway**:
- The C4 pathway was first described by Marshall Davidson Hatch and Charles Rogers Slack. They elucidated this pathway in 1966 in Australia.

5. **Conclusion**:
- Therefore, the correct answer to the question is that the C4 pathway was described for the first time by Marshall Davidson Hatch and Charles Rogers Slack.

### Final Answer:
The C4 pathway was first described by Marshall Davidson Hatch and Charles Rogers Slack in 1966.

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