小题1:B
小题2:A
小题3:C
小题4:B
小题5:D
小题1:根据文章内容“Scientists wanted to see how well they worked after they ate different kinds of breakfasts.”可知答案为B
小题2:根据文章内容“The result shows that if a person eats a right breakfast , he or she will work better than if he or she has no breakfast.”可知答案为A
小题3:根据文章的内容，可知答案为C
小题4:根据单词的意思，可知答案为B
小题5:根据整个文章可知答案为D