What does it indicate if there is no current flow in a circuit?

When there is no current flow in a circuit, it typically indicates that the circuit is open rather than discussing resistance as irrelevant. In a functioning circuit, current requires a continuous conductive path, and if that path is interrupted, current cannot flow. High resistance in a segment of a circuit can also block current flow, but it doesn't render resistance itself irrelevant; rather, it highlights the importance of resistance and circuit integrity.

Other options suggest alternative scenarios: an overloaded circuit wouldn't necessarily lead to no current flow; an increase in voltage can still result in no current flow if resistance is sufficiently high; and if a circuit is shorted, this would usually lead to an excessive current flow rather than none. Thus, focusing solely on resistance in relation to current flow misses the fundamental issue of circuit continuity.