You are driving a stretch of two-lane road with a solid yellow barrier line beside the centre line. You pass a plaza entrance and then a side street. Which of the two, if either, breaks the solid line?

Correct answer: C. The side street — barrier lines are discontinued where public roads intersect, but are not broken at private or commercial entrances

The side street, not the plaza. Book 11 is explicit: "barrier lines must not be broken at private or commercial entrances, but must be discontinued where public roads intersect or where left channelization is present." So the solid line runs straight past driveways and business entrances, and only stops where a public road meets the highway. That matters when you want to turn left into a shop: the line is unbroken there by design, and it is still a no-passing line, which is what a barrier line means — Book 11 defines it as a line that separates opposing traffic and "denotes a no-passing zone on two-way undivided roadways." A gap in the yellow is a public road, not an invitation.

Source: MTO Driver's Handbook: Ontario Traffic Manual, Book 11 — Pavement, Hazard and Delineation Markings (March 2000), Section 3.7 — Barrier Lines, General