Which may be attached with Adenine base in RNA-

Options

A. Guanine
B. Cytosine
C. Uracil
D. Thymine

Answer

**Step-by-step Solution:**

1. **Identify the context of the question**: The question asks about which base can be attached to adenine in RNA.

2. **Understand the structure of RNA**: RNA (ribonucleic acid) consists of a sugar (ribose), a phosphate group, and nitrogenous bases. The nitrogenous bases in RNA include adenine, guanine, cytosine, and uracil.

3. **Differentiate between purines and pyrimidines**:
- Purines: Adenine (A) and Guanine (G)
- Pyrimidines: Cytosine (C), Uracil (U), and Thymine (T) (Note: Thymine is not present in RNA)

4. **Base pairing rules in RNA**: In RNA, adenine pairs with uracil instead of thymine (which is found in DNA). Guanine pairs with cytosine.

5. **Evaluate the options given**:
- Guanine: This is a purine and does not pair with adenine.
- Cytosine: This is a pyrimidine and does not pair with adenine.
- Uracil: This is a pyrimidine and pairs with adenine in RNA.
- Thymine: This is not present in RNA.

6. **Conclusion**: The correct answer is uracil, as it is the nitrogenous base that pairs with adenine in RNA.

**Final Answer**: Uracil is the nitrogenous base that may be attached to adenine in RNA.

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