As heat and pressure increase, ductile deformation becomes less likely becomes more likely is replaced by elastic deformation stops occurring

becomes more likely

Explanation:

Deformation is said to be the change in shape, texture or pattern of a particular body. In relation to geography, the rock becomes the body. It might be extensive as in geologic structure like folds and faults or noticeable on a smaller scale as in clay bodies.

Usually, increase in temperature(heat) and pressure supports ductile deformation, the rocks structure for example folds gain the ability to bend without breaking . The high temperature and pressure experience in the earths warranted the ductility.  

Lower temperature and pressure support brittle deformation , with limited stress the rock structure breaks.

answer; (d) melting of sea ice;