The correct answer is $\boxed{\text{B. }110}$.
The sequence is a list of binary numbers, where each number is formed by the previous number with one additional bit set to 1. For example, $11$ is formed by setting the rightmost bit of $10$ to 1, and $100$ is formed by setting the rightmost bit of $11$ to 1.
Option A, $101$, is not in the sequence because it does not follow the pattern of each number being formed by the previous number with one additional bit set to 1.
Option B, $110$, is in
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