A nucleic acid enzyme is

Options

A. Lysozyme
B. Ribozyme
C. Ribonucleases-P
D. Both B and C.

Answer

**Step-by-Step Solution:**

1. **Understanding Enzymes**: Enzymes are typically proteins that act as biocatalysts to accelerate biochemical reactions. However, there are exceptions where nucleic acids can also function as enzymes.

2. **Identifying Nucleic Acid Enzymes**: The two main types of nucleic acid enzymes are ribozymes and ribonuclease P.
- **Ribozymes**: These are RNA molecules that have catalytic properties. They play a crucial role in processes such as protein translation. An example is the peptidyl transferase, which is involved in forming peptide bonds during protein synthesis.
- **Ribonuclease P**: This is another RNA enzyme that is involved in the processing of tRNA molecules.

3. **Conclusion**: Given the question asks for a nucleic acid enzyme, both ribozymes and ribonuclease P qualify as they are enzymes made of RNA, which is a type of nucleic acid.

4. **Selecting the Correct Answer**: If the options provided include ribozymes and ribonuclease P, then the correct answer would be both B and C (if these correspond to ribozyme and ribonuclease P, respectively). Therefore, the correct option would be option number 4, which includes both.

**Final Answer**: The nucleic acid enzymes are ribozymes and ribonuclease P. The correct option is 4 (both B and C).

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