Assertion : All expression vectors are cloning vectors and vise versa.
Reason : Expression vectors have at least the regulatory sequences i.e., promotes, operators, ribosomal binding sites, etc having optimum function in the chosen control but not origin of replication.

Answer

D

Explanation

All vectors used for propagation of DNA insertes in a suitable host are called cloning vectors. But when a vecor is designed for the expression i.e, production of the protein. Specified by the DNA insert, it is termed as expression vector. Expression vectors need regulatory machinery suitable for the host, e.g., if an eukaryotic gene is to be expressed in prokaryotes, the expression vectors should contain gene without introns because prokaryotes lack introns removal mechinery for transcripts. But all vectors, including expression vectors must contain 'origin of replication' so that they can replicate when the host cell divides and their presence is ensured in all progeny.