When do motorists not have to yield to bicycle traffic?

Motorists do not have to yield to bicycle traffic when there are no cyclists present. The law requires drivers to yield to bicycles only when they are actually on the roadway or lane that the motorists are using. If there are no cyclists in the vicinity, there is no need to yield, as the obligation applies only when both types of traffic are present.

In various contexts, scenarios like marked bicycle lanes or the presence of traffic signals may implicate specific yielding requirements. However, if there are no bicycles, these conditions don't necessitate yielding, which is why this option is the correct answer.