RNA does not possess

Options

A. uracil
B. thymine
C. adenine
D. cytosine

Explanation

**Step-by-Step Solution:**

1. **Understanding RNA Composition**: RNA, or ribonucleic acid, is a type of nucleic acid that plays a crucial role in coding, decoding, regulation, and expression of genes. It is composed of three main components: ribose sugar, phosphate group, and nitrogenous bases.

2. **Identifying Nitrogenous Bases**: RNA contains four nitrogenous bases. These are:
- Adenine (A)
- Uracil (U)
- Guanine (G)
- Cytosine (C)

3. **Comparing RNA and DNA**: It is important to differentiate RNA from DNA (deoxyribonucleic acid). DNA contains:
- Thymine (T) instead of uracil
- Deoxyribose sugar instead of ribose sugar

4. **Analyzing the Options**: The question asks which of the following is not present in RNA: uracil, thiamine, adenine, and cytosine.
- Uracil is present in RNA.
- Adenine is present in RNA.
- Cytosine is present in RNA.
- Thiamine is not present in RNA; it is found in DNA.

5. **Conclusion**: Therefore, the correct answer to the question "RNA does not possess" is **thiamine**.

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