Equilibrium: the Figure Shows Two Forces, Each of Magnitude 4

Multiple Choice

Equilibrium: The figure shows two forces, each of magnitude 4.6 N, acting on an object. The angle between these forces is 40°, and they make equal angles above and below the horizontal. What third force will cause the object to be in equilibrium (acceleration equals zero) ?

A) 8.6 N pointing to the right
B) 7.0 N pointing to the right
C) 4.3 N pointing to the right
D) 3.5 N pointing to the right