By the time we reach adulthood, we have formed a core group of food that contains basic items, which account for 75 percent of our food preferences and intake. a. 40–50 b. 70–80 c. about 100 d. 120–150

The answer to this question is the letter "C" which is "about 100". Hence by the time that we have reached adulthood and we already have formed a core group of food that contains the basic 100 or about 10 basic items which account for 75 percent of our food preferences and intake and the remaining 25 percent for the food that we intake that we did not plan.