Law of limiting factors in photosynthesis was given by:

Options

A. R.Hill
B. Calvin
C. Krebs
D. Blackman

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who proposed the law of limiting factors in photosynthesis.

2. **Identifying the Options**: The options provided are:
- A) Arhel
- B) Calvin
- C) Krebs
- D) Blackman

3. **Recalling Relevant Information**: The law of limiting factors states that in any chemical process (including photosynthesis), if more than one factor is affecting the process, the rate of that process will be determined by the factor that is in the least supply (or minimum value).

4. **Identifying the Correct Scientist**: The law of limiting factors was proposed by the scientist named Blackman in the year 1905.

5. **Eliminating Other Options**:
- Arhel is not associated with this law.
- Calvin is known for the Calvin cycle, which is related to the dark reactions of photosynthesis.
- Krebs is associated with the Krebs cycle in aerobic respiration.

6. **Conclusion**: Based on the information gathered, the correct answer to the question is option D) Blackman.

**Final Answer**: The law of limiting factors in photosynthesis was given by Blackman.

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