Which two things occur when electric charges move through a conductor? A. The field is perpendicular to the electron flow.

B. The field is parallel to the electron flow.

C. An electric field forms.

D. A magnetic field forms.

The two correct answers are A and D ap3x approved!

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current