Ans. Option (a).
Genetic engineering involves intentional modification of the characteristics of a target organism by the manipulation of its DNA or genetic material.
It includes five steps: isolation of target gene; formation of recombinant DNA molecule by joining target gene and vector molecule; insertion of recombinant DNA (vector and target DNA) to host cell; production of many copies of recombinant DNA molecule in host cell; separation and purification of target gene product from host body.
Hence, according to given diagram, step 2 describes cutting of target DNA and vector molecule to get desired fragments, which are then ligated with the ligase enzyme to make a recombinant DNA.
Thus, the correct answer is option (a).