The Fact That Limited Use of Caffeine Can Improve Mental

Multiple Choice

The fact that limited use of caffeine can improve mental alertness and help performance,while excessive use of caffeine can cause anxiety and trembling shows _____.

A) that coffee is an inferior good
B) the law of diminishing marginal returns with respect to test performance
C) the law of returns to scale with respect to test performance
D) decreasing returns to scale in coffee production