Which of the following statement is wrong for viroids?

Options

A. They lack a protein coat
B. They are smaller than viruses
C. They cause infection
D. Their RNA is of high molecular weight

Answer

To determine which statement is wrong for viroids, we need to analyze each option provided in the question. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand what viroids are
Viroids are infectious agents that primarily affect plants. They consist solely of a short strand of circular RNA and do not have a protein coat, which distinguishes them from viruses.

### Step 2: Evaluate the statements
1. **They lack a protein coat.**
- This statement is **correct**. Viroids do not have a protein coat (capsid) surrounding their RNA.

2. **They are smaller than viruses.**
- This statement is also **correct**. Viroids are indeed smaller than most viruses.

3. **They cause infection in plants.**
- This statement is **correct** as well. Viroids are known to cause diseases in various plant species.

4. **Their RNA is of high molecular weight.**
- This statement is **wrong**. Viroids have RNA of low molecular weight, not high molecular weight.

### Step 3: Identify the wrong statement
Based on the evaluation, the wrong statement regarding viroids is: **"Their RNA is of high molecular weight."**

### Conclusion
The correct answer to the question is that the statement about viroids having RNA of high molecular weight is incorrect.

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