A Proton Initially Moves Left to Right Long the X

A proton initially moves left to right long the x axis at a speed of 2.00 * 10³ m/s. It moves into an electric field, which points in the negative x direction, and travels a distance of 0.300 m before coming to rest. If the proton's mass and charge are 1.67 *10 ^{- 27} kg and 1.60 *10 ^{- 19} C, respectively, what is the magnitude of the electric field?

A) 13.9 N/C
B) 0.0696 N/C
C) 28.3 N/C
D) 0.104 N/C