Agarose gel electrophoresis is employed to check the progression of a restriction enzyme .......

Explanation

### Step-by-Step Solution:

1. **Understanding Restriction Enzymes**:
- Restriction enzymes, also known as molecular scissors, are enzymes that cut DNA at specific sequences known as palindromic sequences. These enzymes are crucial in molecular biology for manipulating DNA.

2. **DNA Fragmentation**:
- When a restriction enzyme acts on a DNA molecule, it cleaves the DNA into smaller fragments. The size of these fragments depends on the location of the restriction sites within the DNA sequence.

...