Phosphodiester bond is present in

Options

A. A) ATP
B. B) ADP
C. C) C-AMP
D. D) none of these

Answer

To answer the question "Phosphodiester bond is present in," we need to analyze the options provided and understand what a phosphodiester bond is.

### Step-by-Step Solution:

1. **Understanding Phosphodiester Bonds**:
- A phosphodiester bond is a type of covalent bond that links the phosphate group of one nucleotide to the hydroxyl group on the sugar of another nucleotide. This bond is crucial in forming the backbone of nucleic acids like DNA and RNA.

2. **Analyzing the Options**:
- **Option A: ADP (Adenosine Diphosphate)**:
- ADP contains phosphate groups, but it does not have a phosphodiester bond because it is not a nucleic acid.
- **Option B: ADP (Adenosine Diphosphate)**:
- This is a repeat of option A, and the same reasoning applies.
- **Option C: Cyclic Adenosine Monophosphate (cAMP)**:
- cAMP is a derivative of ATP and contains a phosphate group, but it does not have a phosphodiester bond in the same way that DNA and RNA do.
- **Option D: None of these**:
- Since none of the previous options contain phosphodiester bonds, this option is the most accurate.

3. **Conclusion**:
- The correct answer is **Option D: None of these**, as phosphodiester bonds are primarily found in the backbone of DNA and RNA, not in the options provided.

### Final Answer:
The phosphodiester bond is present in **Option D: None of these**.

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