DDT -
A. is a non-degradable pollutant
B. shows biomagnification
C. is harmful to fishes and birds
D. is a pesticide

Options

A. Only D is correct
B. Only B and C are correct
C. None is correct
D. All are correct

Answer

To solve the question regarding DDT, we will analyze each option provided and determine if it is true or false based on the information about DDT.

### Step-by-Step Solution:

1. **Understanding DDT**:
- DDT stands for Dichloro-Diphenyl-Trichloroethane, which is a synthetic pesticide used for controlling insects.

2. **Option A: DDT is a non-degradable pollutant**:
- DDT is indeed a non-degradable pollutant. It does not break down easily in the environment, leading to long-term ecological effects.
- **Conclusion**: True.

3. **Option B: DDT shows biomagnification**:
- Biomagnification refers to the increasing concentration of a substance, such as a pesticide, in the tissues of organisms at each successive level of the food chain. DDT accumulates in the fatty tissues of animals and magnifies as it moves up the food chain.
- **Conclusion**: True.

4. **Option C: DDT is harmful to fishes and birds**:
- DDT is known to have harmful effects on wildlife, particularly birds and aquatic life. It can cause thinning of eggshells in birds and can be lethal to fish.
- **Conclusion**: True.

5. **Option D: DDT is a pesticide**:
- DDT is classified as a pesticide, specifically used for agricultural and vector control purposes.
- **Conclusion**: True.

### Final Answer:
All options (A, B, C, D) are correct regarding DDT.

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