What would likely happen if an open circuit is closed?

When an open circuit is closed, the continuity of the electrical pathway is restored, allowing electric current to flow through the circuit. This occurs because closing the circuit eliminates the break that was previously present, enabling charge carriers (typically electrons) to move freely from the power source, through the load (like a resistor or light bulb), and back to the power source.

The closing of the circuit creates a complete loop, which is essential for current to exist. Thus, once the circuit is closed, the power source can exert its voltage on the circuit, leading to current flow proportional to the resistance within the circuit according to Ohm's Law. This is why the correct answer is that current will begin to flow once the circuit is closed.

In other scenarios, such as if the circuit remains open, there would be no current flow, and if components were to short circuit, it typically implies that there was a previously functioning circuit that became damaged, rather than a direct result of merely closing an open circuit. Similarly, a drop in voltage to zero would not occur simply from closing the circuit; rather, voltage will be present as long as a power source is connected properly.