As a Proton Moves in the Direction The $\vec { E }$

As a proton moves in the direction the $\vec { E }$ field lines

A) it is moving from field's low potential to high potential and electric potential energy of the system proton-electric field is increasing.
B) it is moving from field's low potential to high potential and electric potential energy of the system proton-electric field is decreasing.
C) it is moving from field's high potential to low potential and electric potential energy of the system proton-electric field is increasing.
D) it is moving from field's high potential to low potential and electric potential energy of the system proton-electric field is decreasing.
E) both it's the electric potential and electric potential energy of the system proton-electric field remain constant.