If you are going to drive on an expressway, choose an answer:
a. you do not need to plan your trip before starting to drive. the signs on the expressway will tell you everything you need to know.
b. you should plan your trip before getting in your vehicle. you should know exactly where you will get on and get off the expressway.
c. you do not need to plan where you will get on and get off the expressway if you have a navigation system that tells you where to turn.