Which sentence has an error in subject-verb agreement?
a) the pile of leaves that had been sitting at the end of the road for weeks began to decompose slowly.
b) there are entirely too many ketchup bottles in he refrigerator, and some of them must be thrown away.
c) unlike most runners, charles - - even if parched - - would never drink any water at any point during the run.
d) the man, in the next apartment, as well as the people across the hall, have lived in the building since 1960.

pls i need answer asap

Read the following passage: he roamed from chamber to chamber with hurried, unequal, and objectless step. the pallor of his countenance had assumed, if possible, a more ghastly hue— but the luminousness of his eye had utterly gone out. the once occasional huskiness of his tone was heard no more; and a tremulous quaver, as if of extreme terror, habitually characterized his utterance. there were times, indeed, when i thought his unceasingly agitated mind was laboring with some oppressive secret, to divulge which he struggled for the necessary courage. which of the above ideas might be considered foreshadowing? he is wandering all over the chamber his skin tone is really pale his voice is quivering the narrator thinks he is laboring with an oppressive secret