Choose the incorrect option $-$

Assertion : In recombinant $DNA$ technology,human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).
Reason : Both bacteria and yeast multiply very fast to form huge population,which express the desired gene.

$Escherichia$ $coli$ $(E. coli)$ is widely used in biological research because:

$A$: $cDNA$ libraries are important to scientists in human genomics.
$R$: $cDNA$ is a synthetic type of $DNA$ generated from $mRNA$.

The given figure shows the cloning vector $pBR322$. Identify the labels $A, B, C,$ and $D$ correctly.

Which of the following statements is not true?
$I.$ $DNA$, being a hydrophilic molecule, cannot pass through cell membranes.
$II.$ $Agrobacterium$ $tumefaciens$ delivers a piece of $DNA$ known as $'T-DNA'$ in the $Ti$ plasmid, which transforms normal plant cells into tumour cells to produce chemicals against pathogens.
$III.$ Retrovirus, adenovirus, and papillomavirus are also now used as cloning vectors in animals because of their ability to transform normal cells into cancerous cells.
$IV.$ In genetic engineering, $DNA$ from different sources are cut with the same restriction enzymes so that both $DNA$ fragments have the same kind of sticky ends.
Choose the correct option.