If you want to overtake a slow truck on a road with heavy traffic, what should you do?

A、Waiting behind the truck until the driver waved his hand to signal that he could pass.
B、Follow behind closely and keep moving to look at the road ahead.
C、Flashes the lights to let the oncoming cars make their way.
D、Keep a distance from the truck so that you can see in front if you can overtake.