According to the Following Graph, the Activity of the Enzyme

Multiple Choice

According to the following graph, the activity of the enzyme decreases more sharply at high temperature than at low temperature. What are the reasons for this observation? I. As temperature is increased, the substrate binding slowly becomes poorer. II. As temperature is decreased, the enzyme moves more slowly and so reacts more slowly.
III) At higher temperatures, the enzyme is denatured and stops working entirely.
IV) Temperature has no effect on enzyme activity.

A) I only
B) IV only
C) I and III
D) II and III
E) All are correct.