Figure 18.2.1 -Refer to Figure 18.2.1 Above. in Which of the Following

Multiple Choice

Figure 18.2.1
-Refer to Figure 18.2.1 above. In which of the following instances does the reduction in the level of emissions outweigh the harm done from emissions?

A) When the level of emissions is 6 units
B) When the level of emissions is 12 units
C) When the level of emissions is 18 units
D) In all of the cases above