The correct option is B P-III, Q-IV, R-I, S-II
Gel electrophoresis is a technique used to separate macromolecules like DNA based on their size and charge on a gel matrix. Being negatively charged, DNA moves away from the cathode towards the anode. The distance that a DNA molecule travels in the gel is inversely related to its size.
Bacteriophages are viruses which attack bacteria. They insert their genetic material into bacteria and use bacteria’s machinery to produce proteins and make numerous copies of themselves by a process called transduction. Bacteriophages have been genetically engineered to deliver genes into bacterial cells. They have very high copy numbers of their genome within the bacterial cells because of their high number per cell.
Plasmid DNA is extra chromosomal material found in some bacterial cells which can make its copies autonomously. Plasmids have been genetically modified and used as vector DNA. It has a small insert size of 5-25 kb.
AmpR stands for ampicillin resistance gene present in many vectors, which is used as a selectable marker. It is used to eliminate cells which are not transformed and selectively permits the growth of transformants.