Final answer:
A reader should be suspicious of the opening sentence because it presents an opinion as a fact, indicative of bias and not objective information.
Step-by-step explanation:
The opening sentence of the paragraph should raise a careful reader's suspicions because it presents an opinion as a fact. Phrases such as "well-known fact" and "so-called" are usually indicative of opinion or bias rather than objective reality. To practice critical reading and identify bias in news, one needs to distinguish these types of statements from unbiased information.
Moreover, a crucial aspect of media literacy is understanding that certain media platforms, including some online news sites, may exhibit bias through the selection of stories they choose to cover, the sources they cite, or the language they use. The ability to discern between a factual report and one that is intended to persuade is an essential skill for navigating the plethora of information available in the digital age. Being aware of the purpose, author's background, and balance between fact and opinion can help identify potential bias in the information presented.