There are $120$ seats in a row.  What is the fewest number of seats that must be occupied so the next person to be seated must sit next to someone?
$\text{(A)}\ 30 \qquad \text{(B)}\ 40 \qquad \text{(C)}\ 41 \qquad \text{(D)}\ 60 \qquad \text{(E)}\ 119$
Let $p$ be a person seated and $o$ is an empty seat
The pattern of seating that results in the fewest occupied seats is $\text{opoopoopoo...po}$.
We can group the seats in 3s like this: $\text{opo opo opo ... opo}.$
There are a total of $40=\boxed{B}$ groups