Country W has banned

IMO D is correct.

The question asks us to weaken the conclusion. The conclusion; The ban is a success. Why was it a success? Because prices have gone up. This implies that raising prices protects orange growers. The inherent assumption in this argument is that people will by the same amount of orange or more. If the rise in price caused people to buy less oranges, could you say that the increase in price of oranges has protected the growers? No. Then you couldn't come to the conclusion in the argument.
This is what D says, thus, D is correct.

The passage doesn't give us any information about how demand would affect the argument. In fact there are too many things that must be assumed for B to hurt the argument. It is possible that demand can decrease and the farmers still see higher revenue. It is possible that domestic farmers produce more oranges to make up for importers and get more money per orange, and thus, higher revenues in general. Maybe it was only a slight decrease in demand. We can't say anything conclusively because the argument doesn't give us enough information.

I hope this help.

Could you please confirm the OA?

Thanks,

Jared

OA is D

Jared,

Even I selected D but I am not convinced how to discard B.

As you wrote :

The passage doesn't give us any information about how demand would affect the argument. [ For B ]
--->
Similarly
The passage doesn't give us any information about how 'decline in sale' would affect the argument. [ For D ]

In one sense, both the things are same. decline in demand or decline in sale

B has some assumption as you wrote.
Similarly, for D also we have to make some assumptions
e.g.
It might be that even if the sales is decreased, the orange growers make more money because of the increased price.

Finally, what I want to say that

Both B and D are looking same.

I think D is correct option.

The conclusion is to protect orange growers ,providing better marketing scope, so stating increased price(more profilt) was considered indicator of success .

To weaken that statement , action should not be favorable to Orange Growers. So if those increased prices results in low demand then the grower is negatively impacted. so that weakens the conclusion.

What is the source of this Question and why C is wrong here?

paes wrote:Country W has banned importation of oranges from Country V in order to protect Country W's orange growers. Since orange prices in Country W have risen since this ban was instituted, the ban is considered a success.

Which of the following, if true, would cast doubt on the conclusion above?


1. The demand for oranges in Country V has risen.

2. The demand for oranges in Country W has decreased.

3. A freeze in Country V damaged large portions of the orange crop.

4. The rise in Country W's orange prices will lead to a decline in sales of those oranges.

5. Orange growers no longer need to spend advertising money to convince consumers Country W produces superior oranges to Country V.

[spoiler]I am confused between B and D.
Give your reasoning to select one and to discard another.
[/spoiler]