, 2008

An $\emph{arithmetic}$ sequence} is a sequence in which each term after the first is obtained by adding a constant to the previous term. If the first four terms of an arithmetic sequence are $a$, $2a$, $b$, and $a-6-b$ for some numbers $a$ and $b$, then the value of the $100$th term is

(A) $-100$ (B) $-300$ (C) $150$ (D) $-150$ (E) $100$