$ELISA$ is based on:

Humulin is

The vaccine of Hepatitis-$B$ is a

Which of the following techniques is based on the principle of antigen-antibody interaction?

Which types of genetically modified organisms are used in biotechnology for the industrial-scale production of biopharmaceuticals and biological products?

Consider the following statements about insulin.
$I.$ Human insulin is made up of $51$ amino acids arranged in two polypeptide chains.
$II.$ The two polypeptide chains are interconnected by two disulphide bridges.
$III.$ In mammals,including humans,insulin is synthesised as a pro-hormone,which contains an extra stretch called the $C$-peptide.
$IV.$ $C$-peptide is not present in the mature insulin.
Which of the statements given above are correct?