Kayla Was a Participant in a Clinical Study to Determine

Kayla was a participant in a clinical study to determine how much vitamin C cures scurvy, the vitamin's deficiency disease. During the study, Kayla consumed only a formula diet that was nutritionally complete, except it didn't contain vitamin C. Within a few weeks, Kayla developed scurvy. At that point, researchers gave 2 mg vitamin C to Kayla each day for a week, but her signs and symptoms of scurvy remained. In the weeks that followed, the scientists continued to increase Kayla's intake of the vitamin by 2 mg/week. After a week of taking 10 mg of vitamin C/day, Kayla reported feeling much better. Based on this information, the researchers concluded that Kayla's

A) requirement for vitamin C was 10 mg.
B) EER for vitamin C was about 10 mg.
C) RDA for vitamin C was 10 mg, plus 15 mg as a margin of safety.
D) AI for vitamin C was 100 mg, which was 10 times the amount that cured her case of scurvy.