Prethinking : The authors arguments is that the tourists are responsible for heavy littering in Downtown Rosco Lake area. Since it is the fourth of July weekend, may be the locals visited the lake area to see the fireworks and caused the littering.
(A) Usually community volunteers go through downtown on Monday mornings, picking up litter.
This option presents an information that is unrelated the authors argument. If this option is true, then the community volunteers will pick the litter as usual and doesn't have an impact on authors argument.
INCORRECT(B) There is a certain correlation between tourist traffic and incidents of vandalism in many towns.
This presents generic information of all towns and is unrelated to the authors arguments which says tourists caused the heavy littering.
INCORRECT(C) During other weekends in July, there were no unusual amounts of litter.
This aligns with the prethinking. If the local visited the lake area, they would account for the more littering and not the tourists. This weakens the authors argument.
(D) The North Shore lakefront area in Rosco Lake is rarely visited by tourists, and has almost no litter, compared to the South Shore, which is a tourist area, and has lots of rubbish lying around.
The authors argument is specific to fourth of July weekend and this option doesn't provide any information on that.
INCORRECT(E) The nearby town of Graylord was able to control its litter problem by instituting large fines that could be levied against litterers.
The authors argument is specific to fourth of July weekend and this option doesn't provide any information on that.
INCORRECTHence
option C