The main role of DNA in a living system is

Options

A. It is the structural material of cell walls
B. It is an enzyme
C. It carries the hereditary characteristics of the organism
D. It participates in cellular respiration

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of DNA**: The primary function of DNA (deoxyribonucleic acid) in living organisms is to store and transmit genetic information. It serves as the blueprint for the development, functioning, growth, and reproduction of all known living organisms.

2. **Evaluating the Options**: The question provides four options (A, B, C, D) regarding the role of DNA. We need to analyze each option to determine which one accurately describes the main role of DNA.

- **Option A**: "A structural material of the cell wall" - This is incorrect because DNA is not a structural component of the cell wall; it is primarily genetic material.

- **Option B**: "An enzyme" - This is also incorrect. DNA itself is not an enzyme; enzymes are typically proteins that catalyze biochemical reactions.

- **Option C**: "Carries the hereditary characteristics of organisms" - This is correct. DNA is responsible for carrying genetic information and hereditary traits from one generation to the next.

- **Option D**: "Participates in cellular respiration" - This is incorrect as DNA does not directly participate in cellular respiration; that process primarily involves other molecules like glucose and oxygen.

3. **Conclusion**: After evaluating all options, it is clear that the main role of DNA in a living system is to carry the hereditary characteristics of organisms. Therefore, the correct answer is **C**.

**Final Answer**: C - Carries the hereditary characteristics of organisms.

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