Historians create ideas we call "history," which are derived from an

Historians create ideas we call "history," which are derived from an order existing in the real world of historical fact. Since the patterns discovered in that world depend in part on the aims of the investigator, however, historical periods will tend to be defined in incompatible ways by historians with different interests. Thus, insofar as the aims of historians of music, painting, literature, and poetry are different, it cannot be assumed that

The passage ends with a statement that begins with "thus." So, the correct answer must complete a conclusion that follows from what the passage says. In other words, the correct answer must be something such that the passage indicates that it "cannot be assumed."

So, basically, we are looking for a choice such that, given what the passage says, that choice is likely NOT true.

A. real-world facts about art will ever be accurately represented

Notice that the facts that "historical periods will tend to be defined in incompatible ways by historians with different interests" and "the aims of historians of music, painting, literature, and poetry are different" do not mean it is not the case that "real-world facts about art will ever be accurately represented."

After all, even if historians define historical periods in "incompatible" ways and have different aims, it is quite possible that, at least sometimes, a historian will define a period "accurately."

Eliminate.

B. the accounts of these historians will ever be anything but arbitrary

Notice that the facts that "historical periods will tend to be defined in incompatible ways by historians with different interests" and "the aims of historians of music, painting, literature, and poetry are different" do not mean it is not the case that "the accounts of these historians will ever be anything but arbitrary (based on an idea or chance rather than reason)."

After all, even if historians define historical periods in "incompatible" ways and have different aims, it is possible that they will based their accounts on reason.

Eliminate.

C. the periods of artistic style delineated by these historians will coincide

Notice that the idea that "it cannot be assumed that" "the periods of artistic style delineated by these historians will coincide (be the same)" follows from what the passage says.

After all, if if historians define historical periods in "incompatible" ways and have different aims, then it seems likely that the periods of artistic style delineated by these historians will NOT coincide.

So, the idea that "the periods of artistic style delineated by these historians WILL coincide" could very likely be incorrect given what the passage says.

Keep.

D. the historical patterns defined by these historians will differ appreciably

Rather than follow from the passage, the idea that "it cannot be assumed that" "the historical patterns defined by these historians will differ appreciably" seems unlikely to be true given what the passage says.

After all, if historians define historical periods in "incompatible" ways and have different aims, then it makes sense to assume that, at least in some cases, "the historical patterns defined by these historians will differ appreciably."

Eliminate.

E. there are any facts from which patterns of artistic style may be derived

Rather than follow from the passage, the idea that "it cannot be assumed that" "there are any facts from which patterns of artistic style may be derived" conflicts with what the passage says.

After all the passage says, "Historians create ideas we call "history," which are derived from an order existing in the real world of historical fact. Since the patterns discovered in that world depend in part on the aims of the investigator ...."

We see that the passage indicates that the "ideas we call 'history'" are derived from fact and that historians discover "patterns," meaning that the patterns exist in the world of fact before they are discovered by historians.

Eliminate.

The correct answer is (C).