Restriction endonucleases are:

$A$ set of bacterial clones,each containing a plasmid or phage,is called

$I.$ Bacteriophages are $...A...$ infecting $...B....$
$II. ...C...$ are hybrid vectors derived from plasmids which contain $cos$ site of $\lambda$ phage.
$A, B$ and $C$ in above statements refer to:

What is the function of $rop$ in a cloning vector?

The restriction enzyme $EcoRI$ cuts $DNA$ at the recognition site $GAATTC$ between which two bases?

The most commonly used enzyme for polymerase chain reaction is