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.

• A
  $Only\; I$
• B
  $Only\; II$
• C
  $Only\; III$
• D
  $Only\; IV$