Why is C correct? Why is B incorrect?

Hi @Ryan-Mahabir, (C) is correct. A hypothesis is a proposed explanation for something, made on the basis of little evidence, that is the jumping off point for more research. This sentence states that the proliferation of arguments is the evidence behind the possible theory that the principles of mechanism are in tension with democracy. The next sentence of the argument then challenges this hypothesis. (B) is incorrect because the argument does not seek to “explain” the proposition established in the sentence. Rather, the next sentence looks to contradict that the proposition.

Hi Annie, is it correct to use the keyword "but" as a pivot language and conclude the author is not in agreement with the proponents? thank you