The role of DNA ligase in the construction of a recombinant DNA molecule is :

Options

A. formation of phosphodiester bond between two DNA fragments
B. formation of hydrogen bonds between stickly ends of DNA fragements
C. ligation of all purine and py rimidine bases.
D. None of the above.

Explanation

### Step-by-Step Solution:

1. **Understanding Recombinant DNA**:
- Recombinant DNA is a DNA molecule formed by combining genetic material from two different species. This process is crucial in biotechnology for creating organisms with desirable traits.

2. **Role of DNA Ligase**:
- DNA ligase is an enzyme that plays a vital role in the formation of recombinant DNA. It is often referred to as "genetic glue" because of its function in joining DNA fragments.

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