Awell-thrown ball is caught in a well-padded mitt. if the deceleration of the ball is 2.10×10^{4} 4 m/s^{2} 2 , and 1.85 ms (1 ms =10^{-3} −3 s) elapses from the time the ball first touches the mitt until it stops, what was the initial velocity of the ball?

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