Which statement explains why sports drinks can be during physical activity? a they provide water and proteins. b they provide proteins and caffeine. c they replenish caffeine and electrolytes. d they replenish electrolytes and carbohydrates.

The correct answer should be D They replenish electrolytes and carbohydrates.

Carbohydrates are important when working out because they are a source of quick energy which is why athletes eat things like pasta often. Electrolytes are important for keeping the body well hydrated. Sports drinks contain these but they are often synthetic and actually do more harm than good.

Blood transfusions were rarely done and often fatal; they were outlawed until the nineteenth century.