Chemical mutagens mostly induce

Options

A. Chromosomal mutations
B. Change in the number of chromosomes
C. Gene mutations
D. Formation of polyploids

Answer

To answer the question "Chemical mutagens mostly induce," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chemical Mutagens**:
- Chemical mutagens are substances that can cause changes in the DNA sequence of an organism. They can induce mutations by altering the structure of DNA.

2. **Types of Mutations**:
- Mutations can be classified into several categories, including chromosomal mutations, gene mutations, and changes in chromosome number (aneuploidy or polyploidy).

3. **Identifying the Type of Mutation Induced by Chemical Mutagens**:
- Chemical mutagens primarily induce **gene mutations**, specifically point mutations. A point mutation involves the alteration of a single base pair in the DNA sequence.

4. **Evaluating the Options**:
- **Chromosomal mutations**: These involve larger changes in the structure or number of chromosomes, which are not typically induced by chemical mutagens.
- **Change in the number of chromosomes**: This refers to aneuploidy or polyploidy, which is not directly caused by chemical mutagens.
- **Gene mutation**: This is the correct answer, as it includes point mutations caused by changes in single base pairs.
- **Formation of polyploids**: This refers to organisms having more than two complete sets of chromosomes, which is not induced by chemical mutagens.

5. **Conclusion**:
- Based on the analysis, the correct answer is **gene mutation**.

### Final Answer:
Chemical mutagens mostly induce **gene mutation**.

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