Here's a problem to solve: Red-clay bricks have a density of approximately 2000 kg/m^3. Air has a density of 1 kg/m^3. Which of the following has the lowest mass?

Among the 4 following options, which is the correct answer?

- A: 2 m^3 of bricks
 
- B: 4 m^3 of bricks
 
- C: 6000 m^3 of air
 
- D: 10,000 m^3 of air
 