Accorsing to paragraph 1, which of the following d...

Câu hỏi: Accorsing to paragraph 1, which of the following discoveries was made during the first era in the history of nutrition?

A. Effective techniques of weight loss were determined.

B. Vitamins were synthesized from foods.

C. Certain foods were found to be harmful to good health.

D. Protein was recognized as an essential component of diet.