That's a more general question.
You would have to discuss Reliability and Validity.
Reliability: How many sources of information did you compare with?
Validity: What kind of source did you get your information from? (e.g. a blog would contain invalid information (to an extent it may be correct, but you must consider that acquiring scientific information from a blog is not common practice)).
Anyway, before a question like that in an exam, most of the time they will ask about a specific subject.
e.g.
Assess the discovery of the Neutrino particle and explain how scientists showed their existence.
Depending on your sources, you will get different answers.
Then, what follows a question like that would be:
Explain how you assessed the accuracy of scientific information with comparable information on more legit sources.
I hope that clarifies things a little.