A Boat Crosses a Stream Which Is Flowing at 10 $\theta$

Multiple Choice

A boat crosses a stream which is flowing at 10.0 m/s.The driver of the boat wants to cross the river and arrive directly across the river from where he departed (point A to point B) .What boat speed in m/s is needed to go directly across the river if the driver steers upstream with $\theta$ = 30.0 ^$\circ$ as shown?

A) 7.5
B) 10.0
C) 15.0
D) 20.0
E) 25.0