Quickly spinning the handle of a hand generator, kevan is able to light three bulbs in a circuit. when he uses two batteries instead of the generator, the bulbs are very dim. which statement best explains why the batteries are not able to power all three light bulbs like the generator?

the batteries do not make the charges move as much
the generator creates less voltage
the batteries have higher amperage
the generator current is more steady

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