I need to () the gas tank before we drive to New Mexico.

• A. Fill up
• B. Check
• C. Drain
• D. Top off

Answer: (A)

The main idea is choosing a verb that means bringing a vehicle’s fuel tank to full before a trip. Fill up is the natural choice because it specifically describes adding gasoline until the tank is full, which is what you want when getting ready for a long drive to New Mexico. Checking the tank would just mean inspecting it, not increasing the fuel level. Draining would remove fuel, which is the opposite of what you need. Top off can mean bringing the tank to full, but it’s more often used when you’re finishing a fill that’s already in progress; for a clear, complete refill, fill up fits best.