(1) For more than a century automobiles have given us great freedom of mobility, but this freedom has come with enormous costs.
(2) Our reliance on gasoline-powered vehicles resulted in the pollution of our environment.
(3) The world’s nonrenewable fossil fuels are being depleted.
(4) In recent years various efforts have been made to address these problems.
(5) Many jurisdictions have enacted laws limiting automobile emissions and requiring greater fuel efficiency.
(6) Another approach has been to develop alternatives to the traditional automobile.
(7) They have cars that run on hydrogen, which produce no pollution at all,and those that run entirely on electricity.
(8) There are even cars that run on used vegetable oil.
(9) Although none of these alternatives has caught on commercially, one that has is the hybrid vehicle, which runs on a combination of gasoline and electricity.
(10) Hybrids require less gasoline than conventional cars, produce less pollution, and run relatively quietly.
(11) Though more expensive than most conventional cars, they have become increasingly popular since they first appeared on the market several years ago.
(12) Still, hybrids are far from ideal.
(13) Unlike hydrogen vehicle, hybrids require gasoline, so they do use up fossil fuels and produce pollution.
(14) Some experts contend that the main reason the hybrid gets such good mileage is its aerodynamic design and not its mechanical engineering.
(15) If a conventional car were similarly streamlined, however,it would get equally good mileage.
In context, which is the best version of the underlined portion of sentence 7 to replace with “They Have”?
(7) (They have) cars that run on hydrogen, which produce no pollution at all,and those that run entirely on electricity.
B - They developed
C- These include
D- This means
E - For example
I chose answer E, but the answer is actually C. Can someone explain why C is right and why E is wrong? Thanks!
