Human insulin is being commercially produced from a transgenic species of

In which therapeutic method is the functional $ADA-cDNA$ introduced into the patient's lymphocytes?

First biochemical to be produced commercially by microbial cloning and genetic engineering is:

The first clinical gene therapy was given for treating

What are transgenic bacteria? Illustrate using any one example.

Given below is the sequence of events in the production of human insulin by Eli Lilly.
$(a)$ Preparation of two $DNA$ sequences corresponding to chain $A$ and $B$ of human insulin.
$(b)$ Production of chain $A$ and $B$ separately.
$(c)$ Introduction of chains in plasmids of $E. coli$.
$(d)$ Extraction of chain $A$ and $B$ and combining them by creating disulphide bonds.
Choose the correct sequence of events.