I choose B for the following reasons:
Premise 1: price increase and decrease of sales of cigarettes by 10%
Premise 2: previous decrease of sales of cigarettes by 1%
Conclusion: volume of cigarette sales strongly related to price
This is a typical cause-effect argument. To strenghten the argument we need to find an answer that will eliminate any other cause for the stated effect or prove that when the cause happens the effect also happens. Only answer B can do that.
A: out of scope, what happened the following year doesn't not help here
B: this shows that a potential cause for the effect did not actually happen => correct answer
C: does not matter that consumers were not aware that the increase was going to happen
D: weakens the argument by proving the existence of another cause for the same effect
E: a greater variety of cigarettes cannot have an impact on the overall number of cigarette sold, it could have an impact only on a specific brand, but that it not the issue here
Yes I can!