What are `A` and `B` in the following reaction ?

A and B in the following reaction are

A, B and C in the following reaction ?

A and B in the following reactions are

A and B in the following reactions are

What are A,B and C in the following reaction ? Arene diazonium fluoroborate overset(NaNO_2//Cu)underset(Delta)rarr A +B+C

A and B in the following reactions are:

A' and 'B' in the following reactions are :

Identify A and B in the following reaction