Assertion :- Genes are the units of inheritance.
Reason :- They contain the information that is required to express a particular trait in an organism.

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Genes are the units of inheritance." This means that genes are the fundamental units that carry genetic information from one generation to the next.

2. **Understanding the Reason**: The reason provided states that "They contain the information that is required to express a particular trait in an organism." This indicates that genes not only serve as units of inheritance but also hold the necessary information to determine specific characteristics (traits) of an organism.

3. **Analyzing the Relationship**: We need to determine if the reason correctly explains the assertion. Since genes are indeed responsible for passing on traits from parents to offspring, and they contain the information necessary for the expression of these traits, the reason supports the assertion.

4. **Conclusion**: Both the assertion and the reason are true. Furthermore, the reason is a correct explanation of the assertion because it clarifies how genes function as units of inheritance by providing the information needed to express traits.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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