In a circuit, two identical switches S1 and S2 are connected in series with a lightbulb and an ideal battery. A student closes S2 while leaving S1 open and observes that the bulb does not light. Which of the following best explains why the bulb remains dark?
(a) The open switch S1 has such a large resistance that it "uses up" the entire battery voltage, leaving none for the bulb to light.
(b) No continuous conducting path exists; the open S1 interrupts the only possible closed loop.
(c) The potential difference across the bulb is too small because the battery’s emf is split among the two switches.
(d) Charges pile up on the terminals of the open switch, blocking additional charges from reaching the bulb even though the rest of the circuit is closed.