Which of the following restriction enzymes produces blunt ends in $DNA$?

$A$ single strand of nucleic acid ($DNA$ or $RNA$) tagged with a radioactive molecule is called:

Identify the plasmid among the following.

Agarose is extracted from

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.

In the following palindromic base sequences of $DNA$,which one can be cut easily by a particular restriction enzyme?