The hydrocarbons they do emit are less likely to（）ozone.

A.twice as expensive as
B.twice as more expensive as
C.as twice more expensive as
D.as twice expensive as

A.three times as big as
B.three times as bigger as
C.as three times big as
D.as three times gigger as

A.in time of
B.in case of
C.in terms of
D.in honour of