$EcoRI$ cleaves the $DNA$ strands to produce

Which was the first restriction endonuclease isolated and identified?

Restriction endonuclease enzymes are used to:

Match the following columns:

Column-$I$	Column-$II$
$(a) \ Cla \ I$	$(1) \ \text{Antibiotic resistance gene}$
$(b) \ pBR322$	$(2) \ \text{Origin of replication}$
$(c) \ tet^R$	$(3) \ \text{Restriction enzyme}$
$(d) \ ori$	$(4) \ \text{Plasmid}$

The key tools required for the recombinant $DNA$ technology are:
$I.$ Restriction enzymes
$II.$ Polymerase enzymes
$III.$ Ligases
$IV.$ Vectors
$V.$ Host organisms
Select the correct option.

The vector for $T-DNA$ is