Which one is a chemical mutagen?
A. Ethyimethane sulphonate
B. Sodium azide
C. Gamma rays
D) 2,4-D

Options

A. A and B
B. B and C
C. C and D
D. A, B, C,D

Answer

To determine which option is a chemical mutagen from the given choices, let's analyze each one step by step:

### Step 1: Understand the term "chemical mutagen"
A chemical mutagen is a substance that can cause mutations in the DNA of an organism. These mutations can occur through various mechanisms, such as altering the structure of DNA or interfering with DNA replication.

### Step 2: Analyze the options
- **A. Ethylmethane sulfonate (EMS)**: This is a well-known chemical mutagen that is frequently used in genetic research to induce mutations.

- **B. Sodium azide**: This is primarily known as a preservative and is not typically classified as a mutagen. It can be toxic and has some mutagenic effects, but it is not a classic chemical mutagen.

- **C. Gamma rays**: These are a form of ionizing radiation, not a chemical mutagen. They can cause mutations by damaging DNA, but they are physical mutagens, not chemical.

- **D. 2,4-D (2,4-Dichlorophenoxyacetic acid)**: This is a herbicide and is not classified as a chemical mutagen. It can affect plant growth but does not directly induce mutations in the way that chemical mutagens do.

### Step 3: Identify the correct answer
From the analysis, the only option that is a recognized chemical mutagen is **A. Ethylmethane sulfonate (EMS)**.

### Final Answer
The correct answer is **A. Ethylmethane sulfonate (EMS)**.

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