Choose the correct option from given alternative:
Incomplete combustion of coal and petroleum :
(A) increases air pollution.
(B) increases the efficiency of machines.
(C) reduces global warming.
(D) produce poisonous gases.
(A) and (B)
(A) and (D)
(B) and (C)
(C) and (D)
Incomplete combustion of coal and petroleum increases air pollution and produce poisonous gases.
Hence, the correct answer is option (A) and (D).