Assertion : Thick cuticle is mostly present in disease resistant plants.
Reason : Disease causing agents cannot grow on cuticle and cannot invade the cuticle.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Assertion**: The assertion states that "Thick cuticle is mostly present in disease-resistant plants." This indicates that plants that can resist diseases tend to have a thicker layer of cuticle on their leaves.

2. **Understanding the Reason**: The reason provided is that "Disease-causing agents cannot grow on cuticle and cannot invade the cuticle." This suggests that the cuticle serves as a protective barrier against pathogens.

3. **Role of the Cuticle**: The cuticle is a waxy layer covering the leaves of plants. Its primary function is to prevent water loss through transpiration. However, a thicker cuticle also provides additional protection.

4. **Thick Cuticle as a Barrier**: In disease-resistant plants, a thick cuticle acts as a physical barrier that limits the entry of pathogens. It prevents the invasion of disease-causing agents by making it difficult for them to penetrate the leaf surface.

5. **Conclusion**: Both the assertion and the reason are true. The thick cuticle in disease-resistant plants serves as a barrier that prevents the invasion of pathogens, supporting the assertion that these plants are better equipped to resist diseases.

6. **Final Statement**: Therefore, the assertion is true, and the reason correctly explains the assertion.

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