A piece of aluminum and a piece of cotton are rubbed together. The piece of cotton is brought very close to the top of the metal electroscope and the electroscope is permanently charged by induction. What charge does the electroscope have?

Transfer of electrons. hope it !

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