发动机有突爆现象极有可能是使用的汽油（）。

A.有杂质

B.有水分

C.辛烷值过低

D.压缩比过低

Years ago, consumers in Finland began paying an energy tax in the form of two Finland pennies for each unit of energy consumed that came from nonrenewable sources. Following the introduction of this energy tax, there was a steady reduction in the total yearly consumption of energy from nonrenewable sources.
If the statements in the passage are true, then which of the following must on the basis of them be true

A．There was a steady decline in the yearly revenues generated by the energy tax in Finland.

B．There was a steady decline in the total amount of energy consumed each year in Finland.

C．There was a steady increase in the use of renewable energy sources in Finland.

D．The revenues generated by the energy tax were used to promote the use of energy from renewable sources.

E．(E) The use of renewable energy sources in Finland greatly increased relative to the use of nonrenewable energy sources.