If traffic from another roadway is merging onto the roadway you are traveling on, you must

Answer: C — Adjust your speed and position to allow cars to merge

When traffic from another roadway is merging onto the roadway you are traveling on, it is important to adjust your speed and position to allow cars to merge. This means you should slow down and leave room for the merging cars to enter your lane. Options A and B are incorrect because speeding up or changing lanes abruptly could make the situation more dangerous for both merging cars and those already on the roadway. Option D is also incorrect because ignoring the merging traffic could result in a collision. Therefore, the best option is C, to safely adjust your speed and position to allow for a smooth merger of traffic.