Answer:
Viewpoint
Step-by-step explanation:
When a writer is unable to keep their work free of biases, they reveal their viewpoint (point of view) - the perspective from which they write about something. For example, if someone is writing about a historical event, they may side with one side or the other and reveal that in their work. A text that isn't influenced by someone's personal feelings, beliefs, or opinions is called an objective text. The opposite would be a subjective text. A text written by someone who is unable to keep their work free from all personal bias is subjective.