Quote:
would you please revisit explanation of A? how can this be a weakener ? It is written "unlikely"
You're completely correct--I think the post you were referencing accidentally took the counterposition to (A). As (A) stands, it
is a good thing for sales of angora if the angora rabbit isn't threatened by the new disease. However, rather than acting as a real strengthener to the argument, (A) is actually an assumption. This difference is subtle, as assumptions do fundamentally support an argument, but essentially you can think of (A) as a prerequisite the conclusion's success (this
must be true, or the conclusion will be in serious trouble) but not really as an active contributor to its success (because knowing that there
are angora rabbits doesn't actually offer any evidence to support the contention that people will substitute angora for cashmere).
Now, why is B incorrect?
Option (B) falls victim to the same error as option (A). This new information is pretty important to the argument, as if the opposite is true--that people
can tell the difference between cashmere and angora--then it casts doubt on the conclusion, which relies (again) on the idea that people will willingly substitute angora products for cashmere products. However, while knowing from (B) that the two materials are hard for most people to distinguish from one another makes this conclusion
believable, it doesn't really help the conclusion as much as (D). For one thing, most people don't buy cashmere or angora, meaning that even if most people can't tell the difference, the minority of people who actually buy items made of these materials might still be able to distinguish between them. Also, even if we assume they can't practically tell the difference between cashmere and angora, that's not great evidence that they'll buy angora instead--it just opens up the possibility. So while it does somewhat help the conclusion, it's easy to conceive of an answer that does a better job.
Option (D) does that better job in two ways: it discusses buyers of luxury fabrics specifically, and it tells us that for those buyers, cashmere and angora occupy a similar niche. This makes it very believable that an increase in cashmere prices will push would-be cashmere buyers into buying angora and so positively supports the conclusion.
_________________
Ryan Starr
Manhattan Prep
EA,
GMAT, and
GRE Instructor
https://www.manhattanprep.com