Extra uridine rich small sized RNA is

Options

A. 5 S RNA
B. sn RNA
C. sc RNA
D. 5.8 S RNA.

Answer

To solve the question regarding which type of RNA is extra uridine rich and small sized, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Options**: We have four options to consider: 5S RNA, SN RNA, SC RNA, and 5.8S RNA.

2. **Identifying rRNA Types**: The first two options, 5S RNA and 5.8S RNA, are types of ribosomal RNA (rRNA). They are part of the structure of ribosomes but do not specifically indicate being extra uridine rich.

3. **Analyzing SC RNA**: SC RNA is generally associated with signal transduction and is known to be small in size (up to 100 nucleotides). However, it is artificially engineered and does not specifically mention being uridine rich.

4. **Examining SN RNA**: Small Nuclear RNA (SN RNA) is known for being extra uridine rich and is also small in size. This aligns with the question's requirement for extra uridine content.

5. **Conclusion**: Based on the analysis, the correct answer is **SN RNA**, as it is characterized by being extra uridine rich and small sized.

### Final Answer:
**SN RNA**

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