Mostly the yeasts are

Options

A. parasites
B. saprophytes
C. epihpytes
D. symbionts

Answer

**Step-by-Step Solution:**

1. **Understanding Yeasts**: Yeasts are unicellular fungi. They are a type of microorganism that plays a significant role in various ecological processes.

2. **Identifying the Nature of Yeasts**: The nature of yeasts is primarily saprophytic. This means they obtain their nutrients by decomposing dead and decayed organic matter.

3. **Exploring the Options**:
- **Parasites**: Parasites are organisms that live on or inside another organism (the host) and derive nutrients at the host's expense, often harming it. Yeasts do not fit this definition.
- **Saprophytes**: As mentioned, yeasts are classified as saprophytes because they feed on dead organic matter.
- **Epiphytes**: Epiphytes are organisms that grow on the surface of plants and derive moisture and nutrients from the air, not from the plant itself. Yeasts do not grow on plants in this manner.
- **Symbionts**: Symbiotic organisms live in a mutually beneficial relationship with another organism. Yeasts do not typically engage in this type of relationship.

4. **Conclusion**: Based on the definitions and characteristics of the options provided, the correct answer is that yeasts are primarily **saprophytes**.

**Final Answer**: Mostly, the yeasts are **saprophytes**.

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