The contact force is indeed caused by "Contact".
Air resistance is basically a type of friction, which is apparently present providing two object contact.
The rest selections are all interaction force, which is not necessarily caused by contact.
We can solve the problem by using Ohm's law, which states that an Ohmic conductor the following relationship holds:

where

is the potential difference applied to the resistor
I is the current flowing through it
R is the resistance
In our problem, I=4.00 A and

, so the potential difference is
The ball accelerates because of gravity.
A is the correct answer !!!