If you begin to feel sleepy while driving on a long trip, you should do which of the following?

Answer: D — Open a window or vent to let in fresh air

When you start feeling sleepy while driving, the best course of action is to open a window or vent to let in fresh air. Fresh air can help increase alertness and keep you more awake while driving. The stimulation from the fresh air can be a temporary measure to alleviate drowsiness, helping to maintain your focus on the road. In contrast, increasing your speed can be very dangerous, especially if you’re not fully attentive. Driving faster does not help improve alertness and can lead to reckless driving. Therefore, it's crucial to prioritize safety by managing drowsiness appropriately rather than resorting to speeding or other ineffective measures.