Which two $DNA$ molecules were joined to create the first artificial recombinant $DNA$?

Identify the parts $A$ and $B$ from the given figure of the $pBR322$ cloning vector:

Which of the following is correctly matched?

In the given figure of the cloning vector $pBR322$,what do '$P$' and '$Q$' represent respectively?

$A$ - Transformation is a procedure through which a piece of $DNA$ is introduced in a host bacterium.
$R$ - With the help of $PCR$,thousands of $DNA$ copies are formed.

Read the following statements and select the incorrect one:
$(I.)$ Disarmed Agrobacterium is used to deliver desirable gene into plant cell.
$(II.)$ In $\text{EcoRI}$,the letter '$R$' is derived from the name of species.
$(III.)$ Gene therapy is a part of modern biotechnology.
$(IV.)$ $\text{DNA}$ is a hydrophilic molecule,so it can easily pass through cell membrane.