How many times of nucleic acids are present in the living systems?

Options

A. One
B. Two
C. Three
D. Four

Answer

**Step-by-Step Solution:**

1. **Identify the Types of Nucleic Acids**: In living systems, there are two main types of nucleic acids. These are essential biomolecules that play critical roles in genetics and cellular functions.

2. **Define the Types**:
- **DNA (Deoxyribonucleic Acid)**: This nucleic acid is responsible for storing and transmitting genetic information. It is generally more stable and is found predominantly in higher organisms.
- **RNA (Ribonucleic Acid)**: This nucleic acid plays a crucial role in protein synthesis and gene expression. RNA is typically less stable than DNA and is found in various forms in all living organisms, including bacteria.

3. **Conclusion**: Based on the identification and definitions of the two types of nucleic acids, we conclude that there are two types of nucleic acids present in living systems: DNA and RNA.

4. **Final Answer**: Therefore, the answer to the question is that there are **2 types of nucleic acids** in living systems.

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