Which of the following is an example of Purine bases?
(a) Adenine
(b) Cytosine
(c) Thymine
(d) Uracil

Options

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

Answer

To solve the question, "Which of the following is an example of Purine bases?" we need to identify which of the given options is classified as a purine base.

### Step-by-Step Solution:

1. **Understand the Types of Nitrogenous Bases**:
- Nitrogenous bases are categorized into two main types: purines and pyrimidines.
- Purines are larger, double-ring structures, while pyrimidines are smaller, single-ring structures.

2. **Identify Purine Bases**:
- The two purine bases are:
- Adenine (A)
- Guanine (G)

3. **Identify Pyrimidine Bases**:
- The pyrimidine bases include:
- Cytosine (C)
- Thymine (T)
- Uracil (U)

4. **Analyze the Options**:
- Option (a) Adenine: This is a purine base.
- Option (b) Cytosine: This is a pyrimidine base.
- Option (c) Thymine: This is a pyrimidine base.
- Option (d) Uracil: This is a pyrimidine base.

5. **Conclusion**:
- Since only adenine is classified as a purine base, the correct answer is **(a) Adenine**.

### Final Answer:
The example of a purine base is **(a) Adenine**.

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