A diver jumps form a diving platform above a pool. The position of the diver above teh water level is given by where s is measured in feet and t is measured in seconds.             When does the diver hit the water? And what is the diver's velocity at impact with the water? g

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