The correct answer is Subject
Here, it is unknown who would be driving to school. Therefore we need either a pronoun or a noun that would give us the subject.
C. 3::::::::hthfhfjfjfjfjfjjtjtjriirhfh
is dnskndkNdsjsjskhsbdbsjshbd
Answer: (B) Undiscover'd country
Explanation: He is talking as if he dosen't know where death will lead, meaning that he is mostly talking about the undisvover'd country.