Question: Which statement about caffeine as an ergogenic aid is true? Need Assignment Help? a. Caffeine is a mild stimulant that can enhance alertness and concentration. b. Even in low doses, caffeine causes stomach upset, nervousness, irritability, headaches, dehydration, and diarrhea. c. College sports authorities prohibit the use of caffeine in amounts greater than 100 milligrams. d. In safe doses of 700 mg/kg of body weight, it improves performance.