In Ontario, a solid yellow line at the left of your lane means:

Answer: B — It is unsafe to pass

A solid yellow line at the left of your lane indicates that it is generally unsafe to pass. This marking is meant to warn drivers that passing may present dangers, such as oncoming traffic or limited visibility. When you see a solid yellow line, it signifies that you should stay in your lane and not attempt to overtake another vehicle. This helps maintain safety on the road by discouraging risky maneuvers in potentially hazardous situations. Following this rule contributes to safer driving practices and reduces the likelihood of accidents.