When a mutation is limited to the substitution of one nucleotide pair of DNA, it is called as

Options

A. deletion
B. inservation
C. inversion
D. point mutation

Answer

To solve the question, "When a mutation is limited to the substitution of one nucleotide pair of DNA, it is called as," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Mutations**:
- Mutations can be categorized into several types based on how they affect the DNA sequence. The main types include deletion, insertion, inversion, and point mutations.

2. **Define Point Mutation**:
- A point mutation is a specific type of mutation where a single nucleotide pair in the DNA sequence is altered. This can involve the substitution of one nucleotide for another, or it can involve the deletion or insertion of a single nucleotide.

3. **Analyze the Options**:
- **Deletion**: This refers to the removal of one or more nucleotide pairs from the DNA sequence.
- **Insertion**: This refers to the addition of one or more nucleotide pairs into the DNA sequence.
- **Inversion**: This refers to a segment of DNA being flipped or reversed within the sequence.
- **Point Mutation**: This is the correct term for a mutation that involves the substitution of one nucleotide pair.

4. **Identify the Correct Answer**:
- Since the question specifically mentions the substitution of one nucleotide pair, the correct answer is **Point Mutation**.

### Final Answer:
The mutation limited to the substitution of one nucleotide pair of DNA is called a **Point Mutation**.

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