What must you do when entering a highway?

Answer: B — Yield to traffic already on the highway and merge safely

When entering a highway, yielding to traffic already on the highway and merging safely is crucial for maintaining safe driving conditions. This process typically involves using a designated on-ramp, where you will accelerate to match the speed of vehicles already traveling on the highway. By yielding and merging safely, you help ensure a smooth transition for both your vehicle and those already on the highway, reducing the risk of collisions. The option to stop until it is safe to enter can create hazards, as sudden stops can lead to rear-end collisions. Accelerating quickly might seem necessary to merge but can actually create a dangerous situation if it leads to cutting off other drivers. Using hazard lights while merging can confuse other drivers, as hazard lights indicate a vehicle is experiencing issues rather than indicating a merging situation. Thus, safely yielding and merging is the most effective approach to entering a highway.