What Explains the Sharp Drop-Off in Enzyme Activity as the Temperature

What explains the sharp drop-off in enzyme activity as the temperature is raised?

A) At high temperatures, substrates cannot bind as easily to the rapidly moving enzyme molecules.
B) The enzyme concentration decreases at high temperatures as molecules move into the vapor phase.
C) Movement of both substrate and enzyme molecules is so rapid at high temperatures that the residence time of substrates bound to enzyme decreases, which decreases the chances that products can form.
D) The enzyme's three-dimensional structure must be intact for catalysis to occur and becomes disrupted at very high temperatures.
E) The equilibrium point for an enzyme-catalyzed reaction is shifted toward reactants and away from products at higher temperatures.