Assertion: Introduction of alien species is responsible for extinction of indigenous species.
Reason: Alien species have no natural predator. So they causes uncontrolled predation and donot show prudent nature.

Options

A. If both Assertion `&` Reason are True `&` the Reason is a correct explanation of the Assertion.
B. If both Assertion `&` Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason if False.
D. If both Assertion `&` Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the introduction of alien species is responsible for the extinction of indigenous species. This means that when a non-native species is introduced to a new environment, it can negatively impact the native species living there.

2. **Analyzing the Reason**:
- The reason given is that alien species have no natural predators in their new environment. This lack of natural predators allows these species to thrive unchecked, leading to overpopulation and competition with native species for resources.

3. **Connecting Assertion and Reason**:
- Since alien species can outcompete native species for resources (food, space, etc.) and reproduce rapidly without natural checks, they can lead to the decline or extinction of indigenous species. This supports the assertion that the introduction of alien species can cause extinction.

4. **Evaluating the Truth of Both Statements**:
- Both the assertion and the reason are true. The assertion accurately describes the impact of alien species, and the reason correctly explains why this impact occurs.

5. **Determining the Relationship**:
- The reason provided does indeed explain the assertion. The uncontrolled growth of alien species due to the absence of predators leads to the extinction of native species, making the reason a correct explanation for the assertion.

6. **Choosing the Correct Option**:
- Based on the analysis, the correct option is that both the assertion and the reason are true, and the reason is the correct explanation for the assertion.

### Final Answer:
**Option 1: Both assertion and reason are true, and reason is the correct explanation for the assertion.**

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