We want to know which one the following statements combine to make zero. In this case, we will analyze each one of the options:
Option 1: A bird flies 25 feet up in the air. It then flies 25 feet across to its nest.
This one does not gives us zero, because in this case, it would mean that the bird should
be in the same place where it started, and then, would have to fly 25 feet down.
Option B: A car is filled with 10 gallons of gas. Half of the 10 gallons are then used on a day's drive.
This option also does not give us zero as he/she doesn't waste everything he/she filled, just the half.
Option C: A player in a game earns 4 points for getting an answer right. She then earns 4 points for making it around the board.
As she just earns more points, she isn't left with 0 points, instead, she has 8. This option does not give us zero.
Option D: Veronica receives $21 for babysitting. She then spends $21 on a new shirt.
As Veronica wastes everything she earned, then, in this situation the quantities COMBINE TO MAKE ZERO.
