Nylon-66 is not an elastomer; it is a synthetic polymer that belongs to the class of polyamides. Elastomers are polymers that possess rubber-like elasticity, such as natural rubber or synthetic rubbers like polyisoprene.
So, the correct option is (A): Nylon-66 is an example of elastomer.
Neoprene is formed from chloroprene. It is prepared by free radical polymerisation. The monomer of neoprene is chloroprene. It is used for preparing gaskets, conveyor belts etc.