Although I am not an expert in CR and I am frustrated because of my performance in CR, in this example I think I have a say.
The conclusion is that even though safety requirements imposed by law, the data does not support that these impositions actually help in reducing accident rate, nevertheless, more stringent laws on road safety are required.
Hence, any premise from the options which says supports that more stringent laws are really required is the answer.
(A) Safety inspections ensure replacement of worn out tires - Nothing to do with road safety laws
(B) Drivers often become overconfident after their cars have passed a thorough safety inspection - Opposite of the conclusion
(C) The roads in provinces and states with stringent car safety programs are far more congested and therefore dangerous than in other provinces and states - Accident rates are high, may be, because of high congestion, may be an explanation, hence strengthens the conclusion
(D) Psychological studies show that drivers who regularly wear seat belts often come to think of themselves as serious drivers, which for a few people discourages reckless driving - Tells nothing about extra safety regulations
(E) Provinces and states with stringent car safety requirements have, on average, many more kilometers of roads then do other provinces and states - More km = > Less Accident rate per km, I agree with Parul09
Hence (C) is right.
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