which would cause an electric circuit to lack a current?\nopen switch\nclosed switch\nlighted…

Brief Explanations:

In an electric circuit, for current to flow, there must be a complete path. An open switch breaks the circuit path, preventing current flow. A closed switch allows current to pass. Lighted bulbs indicate current is flowing through them, and unlighted bulbs could have various reasons but an open - switch is a definite cause for lack of current.

Answer:

open switch