A historical source can be deemed unreliable if the author appears to unfairly favor a particular side or viewpoint. In this case, the source is ...?

Respuesta :

the third point of view

Answer: Bias

Explanation:

Bias is a tendency in a particular direction, either in favor of or against an issue. If a source is biased, it usually lacks of neutrality and objectivity.

A reliable source is one that provides factual knowledge without giving preference for one thing over another.