Answer
The particle will slow down and curve downward.
Work Step by Step
The force vector is being pulled right and down while the velocity vector is points left. Since the parallel component of the force vector is opposite of the velocity vector, the particle will slow down. The perpendicular of the force vector points down so the particle will move in a downward direction. Since they the force has no upward or downward velocity to go against whereas the parallel component does, the particle will curve.
