Answer: A) Unruly.
Step-by-step explanation: Bias is a tendency to support or be opposed to a person or thing, based in a prejudice or in a personal opinion, this leads to treat the person or thing in a unfair way. In the given sentence, the word that indicates bias is "unruly" because it demonstrates a personal opinion that is partialized and accordingly, it isn't objective. It wouldn't be bias if it just saide "Man Assaults Airline Pilot".