22. Fine particulate matter (PM2.5) is an air ________ that affects people's health such as causing or aggravating respiratory and heart disease.
(A) pollutant
(B) substance
(C) pollution
(D) objector
詳解 (共 3 筆)
未解鎖
Fine particulate mat...
未解鎖
(A) pollutant 汙染物 (B...