An organism that decomposes remains is most likely to utilize which of the following modes of nutrition ?

Options

A. Parasitic
B. Saprotrophic
C. Ingestion
D. Chemosynthesis

Explanation

To determine the mode of nutrition utilized by an organism that decomposes remains, we can analyze the options provided:

1. **Understanding Decomposition**: Decomposers are organisms that break down dead organic matter, returning nutrients to the ecosystem. They play a crucial role in nutrient cycling.

2. **Analyzing the Options**:
- **Parasitic Nutrition**: This mode involves organisms that live on or in a host organism, obtaining nutrients at the host's expense (e.g., tapeworms). This is not applicable to decomposers.
- **Saprotrophic Nutrition**: This mode involves organisms that feed on dead and decaying organic matter, breaking it down into simpler substances. This is the primary mode of nutrition for decomposers like fungi and mushrooms.
- **Ingestion**: This refers to the process of taking in food, typically associated with animals that consume food through a mouth. This does not apply to decomposers.
- **Chemosynthesis**: This is a process where certain organisms convert carbon sources into organic matter without using sunlight, typically found in some bacteria. This is not the mode of nutrition for decomposers.

3. **Conclusion**: Given that decomposers break down dead organic matter, the correct mode of nutrition for an organism that decomposes remains is **saprotrophic nutrition**.

### Final Answer:
The organism that decomposes remains is most likely to utilize **saprotrophic nutrition**.