Law of limiting factors in photosynthesis was given by:
(a) Liebig
(b) Arnon
(c) Blackman
(d) Wilstatter

Options

A. Liebig
B. Arnon
C. Blackman
D. Wilstatter

Answer

To determine who proposed the law of limiting factors in photosynthesis, we can follow these steps:

### Step 1: Understand the Law of Limiting Factors
The law of limiting factors states that the rate of a physiological process (like photosynthesis) is limited by the factor that is in the shortest supply. This means that if one factor is limited, it will restrict the overall rate of the process, regardless of the availability of other factors.

### Step 2: Identify the Contributors
We need to look at the options provided:
- (a) Liebig
- (b) Arnon
- (c) Blackman
- (d) Wilstatter

### Step 3: Analyze Each Option
- **Liebig**: Known for the law of the minimum, which states that growth is limited by the scarcest resource.
- **Arnon**: Made contributions to the understanding of photosynthesis but did not specifically propose the law of limiting factors.
- **Blackman**: Proposed the law of limiting factors in photosynthesis in 1905, emphasizing that each factor has a minimum, optimum, and maximum level.
- **Wilstatter**: Known for his work on chlorophyll and photosynthesis but not specifically for the law of limiting factors.

### Step 4: Conclusion
Based on the analysis, the law of limiting factors in photosynthesis was given by **Blackman**. Therefore, the correct answer is (c) Blackman.

### Final Answer
(c) Blackman

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