A : Biological concept of species is based on reproductive isolation
R : Most accepted species concept was given by Linnaeus

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion
C. If Assertion is true statement but Reason is false
D. If both Assertion and Reason are false statements

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the biological concept of species is based on reproductive isolation.
- This means that species are defined by their ability to interbreed and produce viable offspring, while being reproductively isolated from other species.

2. **Analyzing the Biological Species Concept**:
- The biological species concept emphasizes that members of the same species can mate and produce fertile offspring, while members of different species cannot.
- This concept is widely accepted in biology and supports the idea of reproductive isolation as a key factor in defining species.

3. **Understanding the Reason (R)**:
- The reason states that the most accepted species concept was given by Linnaeus.
- However, this statement is incorrect. The biological species concept was primarily developed by Ernst Mayr, not Linnaeus.

4. **Evaluating the Truth of the Statements**:
- The assertion (A) is true because it accurately describes the biological concept of species based on reproductive isolation.
- The reason (R) is false because it incorrectly attributes the concept to Linnaeus instead of Ernst Mayr.

5. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer to the question is that the assertion is true, but the reason is false.

### Final Answer:
- Assertion (A) is true, and Reason (R) is false.

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