Which of the following is correct ?

Options

A. All fungi are filamentous
B. Transfer of DNA from one bacterium to another bacterium cannot take place
C. Viruses cannot have both DNA and RNA together
D. Protists reproduce asexually only

Answer

To solve the question "Which of the following is correct?", we will analyze each option one by one:

### Step-by-Step Solution:

1. **Option A: All fungi are filamentous.**
- Fungi are primarily filamentous in structure, consisting of long chains of cells called hyphae. However, there are exceptions, such as yeast, which are single-celled and do not have hyphae. Therefore, this statement is **incorrect**.

2. **Option B: Transfer of DNA from one bacterium to another bacterium cannot take place.**
- This statement is false because bacteria can transfer DNA to one another through several mechanisms:
- **Conjugation**: where DNA is transferred through direct contact.
- **Transduction**: where DNA is transferred by a bacteriophage (virus).
- **Transformation**: where bacteria take up free DNA from their environment.
Thus, this statement is **incorrect**.

3. **Option C: Viruses cannot have both DNA and RNA together.**
- This statement is correct. Viruses can either have DNA or RNA as their genetic material, but not both at the same time. This is a defining characteristic of viruses. Therefore, this statement is **correct**.

4. **Option D: Proteins reproduce asexually only.**
- This statement is incorrect. Proteins themselves do not reproduce. However, organisms that produce proteins can reproduce both asexually (e.g., binary fission in bacteria) and sexually (e.g., through the formation of gametes). Therefore, this statement is **incorrect**.

### Conclusion:
After analyzing all the options, the correct answer is **Option C: Viruses cannot have both DNA and RNA together**.

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