To weaken the argument for why more single women were sent on mission work in the 1870's, first you have to find that argument. There's a lot of support leading up to it, all about money and who controlled it, but start at line 25:
But as women's groups began raising impressive amounts of money donated specifically in support of single women missionaries, the home churches bowed both to women's changing roles at home and to increasing numbers of single professional missionary women abroad.
The argument for the increase in single women missionaries is that the women's groups raised a lot of money, and that money was influential. Money was the cause.
To weaken that claim, you should prephrase something about the money not being the cause. Look for an alternate cause (some other reason for the increase), the cause without the effect (in an earlier era or another location, women's groups raised a lot of money but the churches still didn't send single women), the effect without the cause (somewhere or sometime else, single women were sent even when they did not have a lot of financial influence), a reversed cause and effect (the money wasn't raised until after the church sent a lot of single women missionaries), or a problem with the data (not sure what that would look like here, honestly, but basically the author just got the facts wrong).
Answer A gives us the effect without the cause. If some churches were sending a lot of single women missionaries but not getting any money from those women's groups, then the money could not have been the cause of the increase, and the argument is weakened.
Did you have another contender in mind? Does that make sense to you now? This should work just like a causal argument in Logical Reasoning. Use those same tools.
Adam M. Tyson
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