Certain hockey players began wearing helmets before the National league required them to do so. These players were 20% less likely to suffer head injuries than other players. Obviously, hockey helmets are critical in preventing head injuries.
Which of the following, if true, would weaken the argument above?
A) Players who began wearing helmets before they were required were, generally, cautious players who were less likely to become involved in rough checking and fights than were other players
B) Early hockey helmets were bulky and uncomfortable, leading some players to complain that they had a negative impact on players' performances
C) Hockey helmets are sometimes constructed from composite materials that provide virtually no cushion from hard shocks
D) Hockey leagues in other countries began requiring helmets more than 20 years earlier, but there are still head injuries in those leagues
E) Hockey helmets do nothing to prevent knee injuries, which are more common than head injuries
Which of the following, if true, would weaken the argument above?
A) Players who began wearing helmets before they were required were, generally, cautious players who were less likely to become involved in rough checking and fights than were other players
B) Early hockey helmets were bulky and uncomfortable, leading some players to complain that they had a negative impact on players' performances
C) Hockey helmets are sometimes constructed from composite materials that provide virtually no cushion from hard shocks
D) Hockey leagues in other countries began requiring helmets more than 20 years earlier, but there are still head injuries in those leagues
E) Hockey helmets do nothing to prevent knee injuries, which are more common than head injuries
