I am denoting $M$ for man and $R$ for rakhsas.
Step 1 : Two rakhsasas row the boat from one side to another. So, one rakshas will reach other side. and one rakhsas will have to row back. So, first side now $(3M + 2R)$ and second side $(1R)$.
So, boat crosses $2$ times.
Step $2 : 2R$ row to other side and leaves one $R$ there and comes back to first side. So, now first side has $(3M + 1R)$ and second side has $(2R)$.
So, boat crosses $2$ times.
Step $3: 2$ $M$ row to other side and gets down at other side. So, first side has $(1R + 1M)$ and second side has $(2M+2R).$
So, boat crosses $1$ time.
Step 4: Now, $1M$ and $1R$ will have to row back from second side, and they will take $1M + 1M$ to other side. So, in the first side, we now have $2R$.
So, boat crosses $2$ times.
Step 5: Last step , $2R$ will row to the other side.
So, boat crosses $1$ time.
Total time boat crosses $=$ $8 +1 = 9$ times.
Correct Answer: $B$