Use of first person pronouns in formal writing may create a sense of familiarity, which a reader may resent.

If the question is to evaluate whether the statement is true or false - it's true.

A formal writing should be objective, and using first person pronouns can give the feeling of subjectivity - and therefore it can take away the seriousness of the argument. Compare "It is accepted that global warming is a fact" and " I accept that global warming is a fact" - the first one sounds more objective and truthful.

Cis the answer for the question