It’s a subcordanating conjunction
The saying means what is considered good is in fact bad and what is considered bad is actually good.
an example could be you trust someone and they seem to be a good person but looks are deceiving and they turn out to be bad
The answer is B. expert authors, the websites you get information from need
to be afficial and have credibility.
hope this helps
The basic questions should be answered in the first paragraph only then details in the rest.
