[求助]这个答案是怎样推理的？急急的！(XDF) 39
| (XDF) 39
A recent survey of all auto accident victims in D Country found that, of the severely injured drivers and front-seat passengers, 80pct were not wearing seat belts at the time of their accidents. This indicates that, by wearing seat belts, drivers and front-seat passengers can greatly reduce their risk of being severely injured if they are in an auto accident.
The conclusion above is not properly drawn unless which of the following is true?
(A) Of all the drivers and front-seat passengers in the survey, more than 20pct were wearing seat belts at the time of their accidents. (这个答案是怎样推理的？) |
