Answer:
A). 'Soaring oil prices and gasoline shortages—peaking with the 1973 Arab Oil Embargo—created a growing interest in lowering the U.S.'s dependence on foreign oil and finding homegrown sources of fuel. '
B). 'Cheap, abundant gasoline and continued improvement in the internal combustion engine hampered demand for alternative fuel vehicles.'
Step-by-step explanation:
Cause-and-effect structure is quite common method employed in descriptive or persuasive writing as such a structure corresponds to explain and persuade the audience more conveniently by providing the logic or reasons(causes) behind a particular effect.
As per the question, options A and B are the excerpts that use a cause-and-effect structure in the given section as they provide the reasons(causes) like 'soaring oil prices..gasoline shortages' led to the effect 'growing interest...lowering U.S.'s dependence on foreign oil, finding homegrown..fuel sources' in option A and similarly option B provides the effect of 'hampered demand for alternative fuel vehicles' that is caused due to 'cheap, abundant gasoline,...continued improvement in internal combustion). Thus, these two excerpt reflect the cause-and-effect structure that elaborates the concern more effectively. Therefore, options A and B are the correct answers.