Which of the following is a genetic RNA ?

Options

A. mRNA
B. rRNA
C. hm- RNA
D. RNA prsent in plant viruses

Answer

To determine which of the following is a genetic RNA, we need to evaluate the options provided. Here’s a step-by-step solution:

### Step 1: Understand the Types of RNA
- **mRNA (Messenger RNA)**: This type of RNA carries genetic information from DNA to the ribosome, where proteins are synthesized. However, it is not considered genetic material itself.
- **rRNA (Ribosomal RNA)**: This RNA forms the core of the ribosome's structure and is essential for protein synthesis. It does not carry genetic information.
- **hnRNA (Heteronuclear RNA)**: This is a precursor to mRNA found in eukaryotic cells. It undergoes processing (splicing, capping) to become mRNA. It is not genetic RNA.

### Step 2: Evaluate the Options
- Based on the definitions:
- **Option A (mRNA)**: Incorrect, as it is not genetic RNA.
- **Option B (rRNA)**: Incorrect, as it does not carry genetic information.
- **Option C (hnRNA)**: Incorrect, as it is a precursor to mRNA and not genetic RNA.

### Step 3: Identify the Correct Answer
- **Option D (RNA present in plant viruses)**: This is the correct answer. In some viruses, RNA serves as the genetic material. For example, certain plant viruses have RNA as their genetic material, and this RNA can be converted into DNA through reverse transcription.

### Conclusion
The correct answer is **Option D: RNA present in plant viruses**, as it is the only type of RNA listed that functions as genetic material.

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