The most thoroughly studied of the known bacteria-plant interactions is the

Which of the following transforms normal plant cells into a tumor?

Explain the following terms in the context of Biotechnology:
$(a)$ $PCR$
$(b)$ Restriction enzymes and $DNA$
$(c)$ Chitinase

Explain the 'cloning sites' in cloning vectors.

The enzyme required for the polymerase chain reaction $(PCR)$ is:

Given below are two statements :-
Statement-$I$ : Restriction endonucleases recognize specific sequences to cut $\text{DNA}$ known as selectable nucleotide sequences.
Statement-$II$ : Restriction endonucleases cut the $\text{DNA}$ 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 :-