IT CAN BE INFERRED FROM THE PASSAGE THAT WHICH OF THE FOLLOWING DISCO...

Câu 5: It can be inferred from the passage that which of the following discoveries was made duringthe first era in the history of nutrition?A.Vitamins were synthesized from foods.B.Effective techniques of weight loss were determined.C.Protein was recognized as an essential component of diet.D.Certain foods were found to be harmful to good health.