Facultative parasites are those which are ?

Options

A. Strictly parasites
B. Usually saprophytes but can also live as parasites
C. Usually parasites but can also lives a saprophytes
D. Strictly saprophytes

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Facultative Parasites":**
- Facultative parasites are organisms that can live both as parasites and as saprophytes. This means they can obtain nutrients from living hosts as well as from dead or decaying organic matter.

2. **Analyzing the Options:**
- The question provides several options regarding the nature of facultative parasites. We need to evaluate each one to determine which is correct.

3. **Evaluating the First Option:**
- The first option states that facultative parasites are "strictly parasites." This is incorrect because facultative parasites are not limited to a parasitic lifestyle; they can also live as saprophytes.

4. **Evaluating the Second Option:**
- The second option states that facultative parasites are "usually saprophytes but also live as parasites." This accurately describes facultative parasites, as they primarily feed on decaying matter but can also derive nutrients from living hosts when necessary.

5. **Evaluating the Third Option:**
- The third option claims that facultative parasites are "usually parasites but also live as saprophytes." This is incorrect since facultative parasites are not primarily parasites; they are usually saprophytes.

6. **Evaluating the Fourth Option:**
- The fourth option states that facultative parasites are "strictly saprophytes." This is also incorrect, as facultative parasites can switch to a parasitic mode of life.

7. **Conclusion:**
- After evaluating all the options, the correct answer is the second option: "usually saprophytes but also live as parasites."

**Final Answer:**
Facultative parasites are those which are usually saprophytes but can also live as parasites.

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