Answer the following question given this paragraph: 

Conversely, very large forces are created by liquids and solids when they try to expand but are constrained from doing so—which is equivalent to compressing them to less than their normal volume. This often occurs when a contained material warms up, since most materials expand when their temperature increases. If the materials are tightly constrained, they deform or break their container. Another very common example occurs when water freezes. Water, unlike most materials, expands when it freezes, and it can easily fracture a boulder, rupture a biological cell, or crack an engine block that gets in its way. Other types of deformations, such as torsion or twisting, behave analogously to the tension, shear, and bulk deformations considered here.


Q: Conversely, very large forces are created by liquids and solids when they try to expand but are constrained from doing so—which is equivalent to compressing them to less than their normal volume. this often occurs when a contained material warms up, since most materials expand when they do this?


A:
increase temperature