Basic unit (monomer) of DNA molecule is

Options

A. nitrogenous base
B. deoxyribose nucleotide
C. deoxyribose-nucleoside
D. pentose sugar

Answer

To answer the question about the basic unit (monomer) of a DNA molecule, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding DNA Structure**:
- DNA (Deoxyribonucleic Acid) is composed of two long strands that form a double helix structure.

2. **Identifying the Components of DNA**:
- DNA is made up of smaller units known as monomers.

3. **Defining the Monomer of DNA**:
- The specific monomer that makes up DNA is called a nucleotide.

4. **Components of a Nucleotide**:
- A nucleotide itself consists of three components:
- A nitrogenous base (which can be adenine, cytosine, guanine, or thymine).
- A deoxyribose sugar.
- A phosphate group.

5. **Conclusion**:
- Therefore, the basic unit (monomer) of a DNA molecule is a nucleotide.

### Final Answer:
The basic unit (monomer) of a DNA molecule is **nucleotide**.

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