The principle of competitive exclusion was stated by

Options

A. C.Darwin
B. G.F. Gause
C. Mac Arthur
D. Verhulst and Pearl

Answer

To answer the question regarding who stated the principle of competitive exclusion, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Principle of Competitive Exclusion**: This principle states that two species competing for the same resources cannot coexist indefinitely. One species will outcompete the other, leading to the exclusion of one species from that niche.

2. **Evaluate the Options**:
- **Option A: Charles Darwin**: He is known for his theory of natural selection, not the principle of competitive exclusion. This option is incorrect.
- **Option B: G. F. Gauss**: He conducted experiments with Paramecium species and observed that when two competing species were grown together, one species outcompeted the other. This led to the formulation of the principle of competitive exclusion. This option is correct.
- **Option C: MacArthur**: He was a military leader and did not contribute to the principle of competitive exclusion. This option is incorrect.
- **Option D: Verhulst and Pearl**: They are known for the logistic growth model, which is unrelated to the principle of competitive exclusion. This option is also incorrect.

3. **Conclusion**: Based on the evaluations, the correct answer is **Option B: G. F. Gauss**.

### Final Answer:
The principle of competitive exclusion was stated by **G. F. Gauss**.

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