Roadways are the most slippery:

1. uring a heavy downpour.
2. fter it has been raining for awhile.
3. The first rain after a dry spell. ✓

Answer: C. The first rain after a dry spell.

The first rain after a dry spell is when roadways are most slippery.

Why this is the answer

The handbook says pavement can be very slippery when rain begins. It singles out the first rain after a dry, hot stretch: the road still holds grime and dust that the rain has not yet rinsed off. That layer makes the surface slicker, so you should slow down as soon as rain starts. The passage does not say a heavy downpour or steady rain later on is the worst case; it points to that first rain after dry weather.

Why the other answers are wrong

• A. uring a heavy downpour. — A heavy downpour makes roads wet, but the passage does not say it is the slipperiest time; it specifically warns about the start of rain after dry weather.
• B. fter it has been raining for awhile. — After rain has continued for a while, water has had time to wash away the grime and dust that make the first rain so slick, so this is not the passage’s answer.

Remember it

Think of the first rain as a warning: slow down when the drops just start.