Assertion : Loss of vigour called inbreeding depression occurs when inbreeding is continued for many generations.
Reason : Quarantine can be done to overcome the harmful effects of inbreeding depression.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true bur reason is false.
D. if both assertion and reason are false.

Explanation

To solve the question regarding the assertion and reason about inbreeding depression, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Loss of vigor called inbreeding depression occurs when inbreeding is continued for many generations."
- Inbreeding refers to the mating of individuals who are closely related, which can lead to a decrease in genetic diversity and vigor over time. This is indeed true, as prolonged inbreeding can result in inbreeding depression, characterized by reduced fitness and health in the offspring.

2. **Understanding the Reason**:
- The reason states that "Quarantine can be done to overcome the harmful effects of inbreeding depression."
- Quarantine typically refers to isolating individuals to prevent the spread of disease or pests. It does not address the genetic issues caused by inbreeding depression. The correct method to overcome inbreeding depression is to introduce new genetic material through crossbreeding or outcrossing, not quarantine.

3. **Evaluating the Truth of Assertion and Reason**:
- Since the assertion is true (inbreeding depression does occur with continued inbreeding), but the reason provided is false (quarantine is not a method to overcome inbreeding depression), we conclude that the assertion is true while the reason is false.

4. **Selecting the Correct Option**:
- Based on the evaluation, the correct option is: "Assertion is true but reason is false."

### Final Answer:
The correct option is: **Assertion is true but reason is false.**

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