Assertion $:-$ The tumor inducing $(Ti)$ plasmid of $Agrobacterium$ $tumefaciens$ has now been modified into a cloning vector.
Reason $:-$ Retroviruses have been disarmed and are now used to deliver genes into animal cells.

Which of the following restriction enzymes used in recombinant $DNA$ technology produces staggered cuts (sticky ends) in $DNA$?

Identify '$U$','$V$' and '$W$' in the given figure of $pBR322$.

Which of the following bacteria is a close relative of $Salmonella$?

'Cloning' is meant for

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.