Most commonly used vector for DNA cloning -

Ans. is 'a' i.e.. Plasmid o A cloning vector is a carrier DNA molecule to which human DNA fragment is attached. Normally, foreign DNA fragments cannot self-replicate within host cell. Therefore, they are joined to a vector DNA, that can replicate within host cell.o The five major types of cloning vectors used are -PlasmidsViral vectors/BacteriophagesCosmidsBacterial Artificial Chromosomes (BACs)Yeast artificial chromosomes (YACs)o Most commonly used vectors are plasmids.