Assertion: Reproductive isolation brings about sympatric speciation
Reason: It is the primary mode of speciation .e.g., Darwin's finches

Options

A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion
C. Assertion is true but Reason is false
D. Both Assertion and Reason are false

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that "Reproductive isolation brings about sympatric speciation."
- **Sympatric speciation** occurs when new species evolve from a single ancestral species while inhabiting the same geographical region. This can happen due to reproductive isolation, where two populations of the same species become unable to interbreed due to various factors such as behavioral differences, temporal isolation, or ecological niches.

### Step 2: Analyze the Reason
The reason states that "It is the primary mode of speciation, e.g., Darwin's finches."
- While reproductive isolation is indeed important for sympatric speciation, the example of **Darwin's finches** actually illustrates **allopatric speciation**. In allopatric speciation, a geographical barrier leads to the separation of populations, which then evolve into different species. The finches evolved due to geographical isolation on the Galapagos Islands, not sympatric speciation.

### Step 3: Conclusion
- Both the assertion and the reason are true statements, but the reason does not correctly explain the assertion. The assertion about reproductive isolation leading to sympatric speciation is correct, but the reason incorrectly identifies Darwin's finches as an example of sympatric speciation when they are actually an example of allopatric speciation.

### Final Answer
Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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