aaba wrote:
Toxic bioaccumulation, a mining hazard induced by the mercury compounds transferred from unrefined cinnabar ore, presently afflicts 7 of every 10 workers in the Redstone Mine. A second mineral which occurs in the same environment, chalcedony, restricts the release of toxins from cinnabar ore. Mining chemists suggest spreading chalcedony in the Redstone Mine in order to preserve the surviving workers.
Which of the following, if true about chalcedony, provides the strongest evidence that the suggestion will be successful?
A It accumulates in deposits which are concentrated in the mineral veins where cinnabar is found.
B It can on some occasions stay inactive in mineral veins for almost five years before it begins to spread.
C It spreads through an environment more gradually than does cinnabar in most geological settings.
D It does not prevent a few common varieties of cinnabar ore from releasing toxins.
E It can occasionally damage fish populations by poisoning their gills.
What is the source of this CR? Doesn't look like an official question. The options are somewhat ambiguous and not easy to comprehend.
Premises:
- Toxins from unrefined cinnabar ore presently afflict 7 of every 10 workers in the Redstone Mine.
- A second mineral which occurs in the same environment, chalcedony, restricts the release of toxins from cinnabar ore.
Mining chemists suggest spreading chalcedony in the Redstone Mine in order to preserve the surviving workers.
We need to say that the suggestion will be successful - so spreading chalcedony will preserve the surviving workers.
A It accumulates in deposits which are concentrated in the mineral veins where cinnabar is found.
This tells us that if we spread chalcedony, it will accumulate in places where cinnabar is found. Well, then it makes it likely that it will be able to stop the toxins from releasing from cinnabar.
Another interpretation could be that it is already found concentrated in places where cinnabar is found. Then how will spreading help and hence the confusion. But since no other option helps, we should take the previous interpretation.
B It can on some occasions stay inactive in mineral veins for almost five years before it begins to spread.
Irrelevant. We are planning on spreading it ourselves. What it does normally we don't care.
C It spreads through an environment more gradually than does cinnabar in most geological settings.
The point is, if we spread it, will it preserve the health of workers? What it normally does is irrelevant.
D It does not prevent a few common varieties of cinnabar ore from releasing toxins.
This weakens our suggestion.
E It can occasionally damage fish populations by poisoning their gills.
Irrelevant.
Answer (A)