Which statement is wrong for viruses

Options

A. All of them have helical symmetry
B. They have ability to synthesize nucleic acids and proteins
C. Antibiotics have no effect on them
D. All are parasites

Answer

To determine which statement is wrong for viruses, we will analyze each of the provided options step by step.

### Step 1: Analyze Option A
**Statement**: All of them have helical symmetry.
**Analysis**: This statement is incorrect because viruses can have different types of symmetry. While some viruses do exhibit helical symmetry, others have icosahedral symmetry or other forms. Therefore, this statement is not universally true for all viruses.

### Step 2: Analyze Option B
**Statement**: They have the ability to synthesize nucleic acids and proteins.
**Analysis**: This statement is also incorrect. Viruses do not have the machinery to synthesize nucleic acids and proteins on their own. They rely on the host cell's machinery to replicate and produce their components. Thus, this statement is wrong.

### Step 3: Analyze Option C
**Statement**: Antibiotics have no effect on them.
**Analysis**: This statement is correct. Antibiotics are designed to target bacterial infections and do not affect viruses. Therefore, this statement is true.

### Step 4: Analyze Option D
**Statement**: All are parasites.
**Analysis**: This statement is partially true. Viruses are obligate parasites, meaning they can only replicate inside a host cell. However, not all viruses are classified strictly as parasites in the traditional sense, as they do not have a metabolic relationship with their hosts like some other parasites do. Thus, this statement can be considered misleading.

### Conclusion
Based on the analysis, the wrong statement about viruses is **Option A**: "All of them have helical symmetry."

### Final Answer
The wrong statement for viruses is **Option A**: All of them have helical symmetry.

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