Zoology - Biotechnology - Principles and Processes Question with Solution | TestHub

Option (3) is the answer because, Kanamycin is an antibiotic which can be used as selectable marker for $E$. coli. Clal is a restriction site on plasmid pBR322. Disarmed retroviruses are used to deliver genes into animal cells, which is an indirect method of gene transfer. Kanamycin ${}^R$ gene exhibits resistance against kanamycin which is an antibiotic.