问题补充：
People in developed countries are supposed more healthy food before than what they have today.
A. to be had
B. to have
C. had
D. to have had
答案：
A. to be had
B. to have
C. had
(答案→)D. to have had
解析：考查非谓语动词。句意：发达国家的人们以前应该享有便现在更健康的食品。不定式表示具体的动作，如果动作发生在谓语动词之前，则要用完成时态的不定式，故选D。
