Which traffic rule is often modified for emergency vehicles responding to calls?

The modification of traffic rules for emergency vehicles is crucial for enabling them to respond quickly to emergencies. When responding to calls with lights and sirens activated, emergency vehicles are permitted to exceed posted speed limits. This allowance is in place because rapid response can be critical in life-threatening situations, allowing first responders to arrive quickly at the scene where their assistance is needed.

While emergency vehicles do have privileges, they must still operate with a heightened sense of caution when exceeding speed limits. The operation of lights and sirens in conjunction with this privilege notifies other road users of their approach, allowing them to yield as appropriate.

In contrast, the other options suggest blanket exemptions from traffic rules, which can pose safety risks. Ignoring speed limits entirely, disregarding all traffic signals, or stopping at all red lights when responding would undermine the rationale for modifying traffic regulations specifically for emergency response. Emergency vehicles must navigate intersections and signals carefully, attempting to minimize the risk to themselves and other road users while ensuring an efficient response.