The correct answer is 4: Cassius cannot believe that a weakling like Caesar has become so great. Cassius complains of being forced to bow before Caesar (he "must bend his body If Caesar carelessly but nod on him"), and the fact that Caesar has suffered from fevers and seizures makes his submission to him all the more enraging. Cassius does not believe himself to be less than any other man, much less one who has such weak health.
"D. My mother or my father is going to pick me up from swim practice" is the only sentence that contains an error in subject-verb agreement, but this is common.
Well, Caliban is clever and quick-thinking