Identify thermosetting polymer from following.

Step-by-step solution

Thermosetting polymers are cross-linked or heavily branched molecules, which on heating undergo extensive cross-linking in moulds and become infusible. These cannot be reused. Examples of thermosetting polymers include Bakelite, urea-formaldehyde resins, and melamine-formaldehyde resins. Polystyrene is a thermoplastic polymer. Buna-S is an elastomer. Terylene is a fibre. Answer: Ureaformaldehyde resin