Which of the foll A. Heavily branched cross linked polymers.

B. Linear slightly branched long chain molecules.

C. Become infusible on moulding so cannot be reused.

D. Soften on heating and harden on cooling, can be reused.

Primarily let us see what does Thermosetting polymers mean, a thermosetting polymer is a polymer which becomes irreversibly hard when it is heated and becomes infusible. Hence it can’t be reused. Polymer initially is a liquid, which under the influence of heat gains energy to undergo the required chemical reactions to increase cross-linking among the polymer chains. Hence we understood why point i and iii stands right as the characteristics. Dealing with point ii we observe that they say ‘linear slightly branched’ which is completely false according to the point which we have proved right in i. Coming to point iv we observe that it is not only completely converse to that of iii, which stands out true, but also a property of thermoplastic hence we conclude that point iv is false.