Which situation typically leads to an open circuit?

An open circuit occurs when there is a break in the conductive path that allows electricity to flow. In this context, a break in a wire connection is a primary cause of an open circuit because it interrupts the continuity of the electrical flow. When a wire is compromised—whether due to physical damage, corrosion, or fatigue—current is unable to travel past that point, resulting in the circuit being open. This means that electrical devices relying on that circuit will not receive power, thereby failing to operate as intended.

In contrast, while excessive moisture can cause short circuits or corrosion, it does not typically lead to an open circuit by itself. Incorrectly matched connectors may prevent devices from working correctly, but they usually do so without creating a discontinuity in the circuit. A worn-out resistor might alter the resistance but generally does not create a full open circuit unless it fails completely. Thus, the scenario of a break in a wire connection is the most straightforward and common case that leads to an open circuit.