Identify the labels $M$ and $N$ in the following agarose gel electrophoresis representation.

Given below are two statements:
Statement $I:$
Restriction endonucleases recognise specific sequences to cut $DNA$,known as palindromic nucleotide sequences.
Statement $II:$
Restriction endonucleases cut the $DNA$ strand a little away from the centre of the palindromic site.
In the light of the above statements,choose the most appropriate answer from the options given below:

Polymerase chain reaction employs

What is true for plasmid?

Recombinant $DNA$ can be obtained by cutting pro-$DNA$ using:

Molecular scissors are