Which situation results in a final value of zero?
A. The overall change in temperature when the temperature goes from -10 degrees fahrenheit, to 10 degrees fahrenheit.

B. The total profit made from when a person buys an item for $2.25, and then sells the item for $2.25.

C. The overall change in altitude in a hot air balloon after rising 21 kilometers from sea level.

D. The total distance a person travels when he bikes 3.1 miles to school and the bikes 3.1 miles back home.