Which microorganism is useful for $PCR$?

Which one of the following is called the polynucleotide joining enzyme?

Which of the following is known as a restriction endonuclease?

Which vector can clone a small fragment of $DNA$?

Identify the desirable characteristics for a plasmid used in $rDNA$ technology from the following.
$A$. Ability to multiply and express outside the host in a bioreactor.
$B$. $A$ highly active promoter
$C$. $A$ site at which replication can be initiated
$D$. One or more identifiable marker genes
$E$. One or more unique restriction sites.

Match the following:

Column-$I$	Column-$II$
$(1)$ Bacterial membrane	$(p)$ Chitinase
$(2)$ Plant cells	$(q)$ Ribonuclease
$(3)$ Fungal membrane	$(r)$ Lysozyme
$(4)$ $RNA$ molecule	$(s)$ Cellulase