According to the passage, which condition should the sources used to test…

Concept: In reading comprehension, an answer should match the criterion explicitly stated in the passage rather than rely on personal preference. A criterion is the property or standard that the passage tells the reader to apply.

Application: The passage says that, to make sure one is dealing with facts, one should seek scientific sources for testing them. The revised stem asks which condition those testing sources should satisfy; therefore, the required condition is being scientific sources.

Contrast:

• Being scientific sources describes the kind of sources the passage directs the reader to seek.

• Being guided by one's emotions makes a personal response the guide instead of describing the testing sources.

• Being guided by one's close relatives makes interpersonal advice the guide instead of describing the testing sources.

• Fudging facts changes the factual record instead of describing the sources used to test it.

Result: The sources used to test facts should be scientific sources.