The Electric Field in the Region Defined by the Y-Z

The electric field in the region defined by the y-z plane and the negative x axis is given by E = −ax, where a is a constant. (There is no field for positive values of x.) As −x increases in magnitude, relative to V = 0 at the origin, the electric potential in the region defined above is

A) a decreasing function proportional to −|x²|.
B) a decreasing function proportional to −|x|.
C) constant.
D) an increasing function proportional to +|x|.
E) an increasing function proportional to +|x²|.