How many basic steps are involved in the creation of a $GMO$?

$DNA$ can be introduced into any cell by:

In which method is recombinant $DNA$ directly injected into the nucleus of an animal cell?

The stirrer in a stirred-tank bioreactor facilitates:

During the process of isolation of $DNA$,chilled ethanol is added to

Study the given figure carefully and select the correct statements regarding this.
$I.$ It represents typical agarose gel electrophoresis showing differential migration of $DNA$ fragments.
$II.$ Lane $1$ contains undigested $DNA$ fragments.
$III.$ Lanes $2$ to $4$ contain digested $DNA$ fragments.
$IV.$ Smallest $DNA$ bands are present at $(A)$ position and largest $DNA$ bands are present at $(B)$ position.