I choose D
(A) The 1974 fuel shortage cut driving sharply for more than a year.- out of scope
(B) There was no decline in the rate of highway fatalities during the twelfth year following the reduction in the speedlimit.
- weakens the argument
(C) Since 1974 automobile manufacturers have been required by law to install lifesaving equipment, such as seat belts, in all new cars.- weakens
(D) The fatality rate in highway accidents involving motorists driving faster than 55 miles per hour
...
(A) The 1974 fuel shortage cut driving sharply for more than a year.- out of scope
(B) There was no decline in the rate of highway fatalities during the twelfth year following the reduction in the speedlimit.
- weakens the argument
(C) Since 1974 automobile manufacturers have been required by law to install lifesaving equipment, such as seat belts, in all new cars.- weakens
(D) The fatality rate in highway accidents involving motorists driving faster than 55 miles per hour
...
