Hi Kelly! Nice job understanding why (C) is a good answer choice. Assuming a causal relationship between two correlated things is
inherently a logical flaw, and that is exactly what the scholar in the stimulus did here.
The flaw contained in answer choice (D), on the other hand, is not present in our argument. (D) is incorrect because the scholar never argues that modernization is the
only way a religion can draw an increased attendance. If the conclusion read, "This shows that such modernization is the only way to result in an increased numbers of worshipers," (D) would be a good answer. In Flaw questions, we need to attack the error that is actually being used in the argument.
I thought that the assumption implicit in any causal conclusion is that the stated cause (modernization) is the only cause of that stated effect (increased number of worshippers).
Be careful here. It's true that the Scholar here is ignoring the other potential factors that may have led to increased attendance in order to focus on the modernization of texts/rituals as the sole cause of those recent increases. However, just because the Scholar in his argument has ignored potential other past causes to form his causal relationship, that doesn't mean that he is necessarily throwing away all other potential present/future causes of increased attendance.
Let's look at another example. A doctor says - "A recent study of 200 patients shows that a diet high in red meat consumption correlates with heart disease. So we know that eating red meat causes heart disease." We can NOT assume that the doctor is saying, "Nothing besides eating red meat can cause heart disease". While the doctor's argument is flawed because it ignores other potential contributing causes among those 200 patients in order to form a causal relationship, that does NOT mean that the doctor is forever tossing out all other potential causes of heart disease.
To sum up: when an argument creates a causal relationship (A causes B) between two correlated things, that is a Flaw. However, the creation of a causal relationship alone does not mean that the author is also saying that only A can ever cause B.
Hope that helps!