Answer: a. Halo effect
Explanation: The halo effect is an inclination for an impression created in one area to influence an opinion in another area. In this type of cognitive bias our overall impression of a person influences how we feel and think about their character. This is exactly what the is experiencing. When our overall impression about the person (or something, or area) is positive (usually inferred from small amounts of information), we will tend to assume that all of their traits will be positive. Same is true for negative impressions. The reason why people experience the halo effect is due to the fact that once an initial impression is formed about something or someone we often try to prove that that impression is right. This action serves a major function, it gives the person who formed that impression a positive feeling of accomplishment.