All viruses are entirely

Options

A. (a) obligate parasites
B. (b) obligate saprophyte
C. (c) facultative parasites
D. (d) non living

Answer

**Step-by-Step Solution:**

1. **Understanding Viruses**: Viruses are unique entities that are not classified as living organisms because they cannot carry out metabolic processes on their own. They require a host cell to replicate and propagate.

2. **Evaluating the Options**:
- **Option A: Obligate Parasites**: This option suggests that viruses are obligate parasites, meaning they must rely on a host organism for their survival and reproduction.
- **Option B: Obligate Saprophytes**: This option implies that viruses feed on dead organic matter, which is not true for viruses.
- **Option C: Facultative Parasites**: This option indicates that viruses can live both independently and as parasites, which is incorrect since viruses cannot survive without a host.
- **Option D: Non-living**: While viruses exhibit some non-living characteristics, they cannot be classified as entirely non-living because they depend on host cells for reproduction.

3. **Conclusion**: After evaluating all options, the correct classification for viruses is that they are **Obligate Parasites** because they entirely depend on host cells for their metabolic processes and reproduction.

**Final Answer**: All viruses are entirely **Obligate Parasites**.

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