The smallest RNA is :-

Options

A. tRNA
B. mRNA
C. rRNA
D. genetic RNA

Answer

To solve the question "The smallest RNA is:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of RNA**:
- RNA stands for ribonucleic acid and is a single-stranded molecule, unlike DNA which is double-stranded.
- There are three main types of RNA:
- **mRNA (messenger RNA)**: carries genetic information from DNA to the ribosome for protein synthesis.
- **tRNA (transfer RNA)**: helps in translating the mRNA sequence into an amino acid sequence by carrying amino acids to the ribosome.
- **rRNA (ribosomal RNA)**: a component of ribosomes that helps in protein synthesis.

2. **Identify the Size of Each RNA Type**:
- Among these types, tRNA is known to be the smallest in terms of nucleotide length.
- mRNA is generally longer as it carries the entire coding sequence for a protein.
- rRNA varies in size but is typically larger than tRNA.

3. **Determine the Correct Answer**:
- Since tRNA is the smallest RNA molecule compared to mRNA and rRNA, the correct answer to the question is tRNA.

### Final Answer:
The smallest RNA is **tRNA (transfer RNA)**.

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