- PowerScore Staff
- Posts: 944
- Joined: Sep 06, 2017
It looks like you're focusing on the wrong part of the stimulus; the key here is understanding the causal relationship posited, which is that production of the white glass caused the accidental discovery of Han purple, because they both used the same ingredients. To make that more likely, we have to tie the two processes together, either by eliminating an alternate cause (which would be hard to Prephrase in this case), or by showing either both the cause and effect together, or no cause, no effect. The other issue is that this is one of the rare stimuli in which reverse causation could potentially be in effect (making Han purple led to discovery of how to make the white glass), so taking that possibility away would be my initial Prephrase.
(A) works to strengthen the causal relationship by showing not only the cause and effect together (which we already knew from the stimulus) but also by showing that that was where most of the production happened, and thus that most other areas of China had no cause (the glass production) and no effect (discovery of Han purple). It is relatively weak evidence, but still strengthens the conclusion (and we can't really expect millennia-old archaeology to help too much).
Contrast that to (D), which makes it more likely that someone would make a chance discovery, as the ingredients were easily obtainable. But we already know a discovery was made; the point we're trying to help is that glass production was the specific, sole actual cause of the discovery of Han purple. The fact that more people would have an opportunity to make glass doesn't make it any more likely that the glass-making was the actual cause for the discovery of Han purple, as it doesn't make it likelier that one thing led to the other; reverse causation could still be in effect, and just as likely.
Hope this clears things up!