At this point, the writer is considering adding the following sentence. Successful nerve impulse transmission depends not only on myelin sheaths, but also on the presence of ion pumps embedded in the cell membrane. Should the writer make this addition here? A) Yes, because it describes how the presence of ion pumps is related to the functions of cholesterol.
B) Yes, because it supports the passage’s main argument with a second example of cholesterol’s potential adverse health effects.
C) No, because it identifies a relationship between the nervous system and ion pumps that has already been discussed.
D) No, because it interrupts the paragraph’s discussion of cholesterol’s functions with loosely related information.

D) No, because it interrupts the paragraph’s discussion of cholesterol’s functions with loosely related information.

Explanation:

The passage was discussing the importance of cholesterol in nerve impulse transmission. Its presence in the myelin sheaths of nerve cells speeds up nerve impulse transmission. It will not be wise for the author to now bring in the relationship between nerve impulse transmission and ion pumps. This is because the main topic under discussion is cholesterol and its importance. The sentence should be continued with other importance of cholesterol and not ion pumps.

significant amounts of nitrogen oxides, carbon monoxide, and other pollution

explanation:

passenger vehicles are a major pollution contributor, producing significant amounts of nitrogen oxides, carbon monoxide, and other pollution. in 2013, transportation contributed more than half of the carbon monoxide and nitrogen oxides, and almost a quarter of the hydrocarbons emitted into our air.

chordata is the answer