A molecule that can act as a genetic material must fulfill the traits given below except.

Options

A. it should be able to express itself in the form of Mendellan characters
B. it should be able to generate its replica
C. it should be unstable structurally and chemically
D. it should provide the scope for slow changes that are required for evolution.

Answer

To solve the question regarding the traits that a molecule must fulfill to act as genetic material, we need to analyze each option provided and determine which one does not align with the characteristics required for a genetic material.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks us to identify which trait is NOT required for a molecule to act as genetic material. We are given four options to evaluate.

2. **Evaluating the Options**:
- **Option A**: "It should be able to express itself in the form of Mendelian characters."
- This is a requirement for genetic material. Genetic material must be able to express traits that can be inherited, which aligns with Mendelian genetics.

- **Option B**: "It should be able to generate its replica."
- This is also a requirement. Genetic material must be capable of replication to ensure that genetic information is passed on during cell division.

- **Option C**: "It should be unstable structurally and chemically."
- This is NOT a requirement. In fact, for a molecule to act as genetic material, it should be stable both structurally and chemically to maintain the integrity of the genetic information over time.

- **Option D**: "It should provide the scope for slow changes that are required for evolution."
- This is a requirement. Genetic material must allow for mutations and variations, which are essential for evolution.

3. **Identifying the Exception**: From the evaluation, we see that Option C ("It should be unstable structurally and chemically") is the only statement that does not align with the necessary traits for a molecule to act as genetic material.

### Conclusion:
The correct answer is **Option C**: "It should be unstable structurally and chemically."

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