Which statement about restriction enzymes is correct?

Correct answer: They cut after recognizing specific DNA sequences

Restriction enzymes are molecular tools that identify a particular DNA sequence, called a recognition sequence, and cleave the DNA at a defined location associated with that sequence. Their action is therefore specific rather than random. This specificity allows researchers to select where a DNA molecule will be opened and to produce useful fragments for cloning, mapping, or analysis. The enzyme responds to the nucleotide sequence, not to unrelated cell structures or simple nutrients.

Option C is correct because it says that the enzyme recognizes specific DNA sequences before cutting. Option A is wrong because cutting does not occur everywhere randomly. Option B describes a cell membrane, which is not the substrate of these enzymes, and option D concerns glucose production, unrelated to restriction activity. Recognition followed by cleavage is the defining idea.