Thermal Expansion: a Machinist Needs to Remove a Tight Fitting

Multiple Choice

Thermal expansion: A machinist needs to remove a tight fitting pin of material A from a hole in a block made of material B. The machinist heats both the pin and the block to the same high temperature and removes the pin easily. What statement relates the coefficient of thermal expansion of material A to that of material B?

A) Material B has a greater coefficient of expansion than does material A.
B) The situation is not possible because heating block B will shrink the hole in the material as the material expands with increasing temperature.
C) Material B has the same coefficient of expansion as does material A.
D) Material A has a greater coefficient of expansion than does material B.