Marine teleosts, undergoing putrefaction, emit sharp characteristic foul odor, which is due to the production of
(a) Trimethylamine
(b) Hydrogen sulfide
(c) Ammonia
(d) Lactic Acid

Options

A. Trimethylamine
B. Hydrogen sulfide
C. Ammonia
D. Lactic Acid

Answer

To solve the question regarding the foul odor emitted by marine teleosts during putrefaction, we will analyze the options provided and identify the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding the Context**: The question mentions marine teleosts undergoing putrefaction, which is a decomposition process that can lead to the release of various compounds.

2. **Identifying the Compounds**: The options given are:
- (a) Trimethylamine
- (b) Hydrogen sulfide
- (c) Ammonia
- (d) Lactic Acid

3. **Analyzing Each Option**:
- **Trimethylamine**: This compound is known for its strong, fishy odor and is often associated with the breakdown of trimethylamine oxide, which is a major excretory product in marine organisms.
- **Hydrogen sulfide**: This gas has a characteristic rotten egg smell and is produced during the decomposition of organic matter, but it is not specifically linked to marine teleosts.
- **Ammonia**: While ammonia can have a strong odor, it is not the primary compound associated with the foul smell in marine teleosts.
- **Lactic Acid**: This compound is produced during anaerobic respiration and does not typically contribute to foul odors associated with putrefaction.

4. **Conclusion**: Based on the analysis, trimethylamine is specifically linked to marine teleosts and is known for its foul odor due to the breakdown of trimethylamine oxide. Therefore, the correct answer is:
- **(a) Trimethylamine**

### Final Answer:
(a) Trimethylamine

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