A Griever is a creature that lives in the Maze and comes out mainly after dark (this is not always the case, they have sometimes been known to come out in the daytime). Its purpose is to harass and even kill the Gladers who venture into the Maze.
For A) to be correct, it should be "The deli Worker gave him and her free slice of ham. For B) to be correct, it should be Eric told them about his Journey. For D) is also wrong! With that being said, C has the correct object pronouns.
They described Boo Radley as a monster. Jem said "Boo was about six-and-a-half feet tall, judging from his tracks; he dined on raw squirrels and any cats he could catch, that's why his hands were bloodstained - if you ate an animal raw, you could never wash the blood off.”