would go with C

as the anti smoking program will be a success if the students are stopping to smoke completely but if they are taking breaks from the school premises to smoke somewhere else then it can't be said that the anti smoking proam was a success ..

Last year, the incidents of students smoking on school premises decreased by over 70%.

thus C, though students are not smoking on school premises, they could be in the school ground thus C

NOT B because it supports the clause of smoking reduction on campus. Students smoking some where else(not on school premises) don't contribute towards the % of smoking on school premises.
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Persistence+Patience+Persistence+Patience=G...O...A...L

I believe, the question is about an "anti-smoking education program" that was implemented last year in all the county schools, not about an "anti-smoking in schools education program".

[Edited because of a typo]

Folks you are missing the point->A system-wide county school anti-smoking education program was instituted last year.

thus C
_________________

Persistence+Patience+Persistence+Patience=G...O...A...L

OA is C
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Persistence+Patience+Persistence+Patience=G...O...A...L

A system-wide county school anti-smoking education program was instituted last year. The program was clearly a success. Last year, the incidents of students smoking on school premises decreased by over 70%.

Which of the following, if true, would most seriously weaken the argument in the passage?

a) The author of this statement is a school system official hoping to generate good publicity for the anti-smoking program.

b) Most students who smoke stopped smoking on school premises last year continued to smoke when away from school.

c) Last year, another policy change made it much easier for students to leave and return to school grounds during the school day.

d) The school system spent more on anti-smoking education program last year than it did in all previous years.

e) The amount of time students spent in anti-smoking education program last year resulted in a reduction of in-class hours devoted to academic subjects.


asn is clearly : c

it is a cause and effect problem
it says that : anti smoking education programme -causes - the reduction of smoking

but for cause and effect problem:

when we weaken the conclusion we need to draw another cause which makes the reduction

and -c- clearly says that.

and in - B- it is not weaken the conclusion rather it strong the conclusion.
bcoz it says that for the anti smoking education programme student dont smoke in the capus.

i think it will help

thanks
shobuj

It is between B and C.

B weakens the conclusion
C weakens the argument

Thanks Billjeans. Your comment nailed it for me. Kudos.