Q1: Enzymes that recognize and cleave specific 4 to 8 base pair sequences of DNA are

ANS:C - restriction endonucleases

DNA Ligase is an enzyme that combines the two adjacent strands.

Helicases is another type of enzyme that cleaves hydrogen bonds present between two polynucleotide strands and it cleaves the entire duplex.

DNA gyrase involves in Negative super coiling after the action of Helicase enzyme.

Restriction endonuclease is an enzyme that cuts double stranded DNA, which makes incisions, one through each of the phosphate back bones of the double helix forming free 3'-OH and 5' phosphate ends. It recognizes and cleave specific 4 to 8 base pair sequences of DNA.