Select the appropriate option regarding $r-DNA$.

Which was the first restriction endonuclease isolated and identified?

What is required for the functioning of a cloning vector $DNA$?

Which of the following methods are used for the analysis of Restriction Fragment Length Polymorphism $(RFLP)$?
$1$. Electrophoresis
$2$. Electroporation
$3$. Methylation
$4$. Restriction digestion

Which enzyme is known as molecular scissors?

Select the appropriate option for agarose.