(C) Biases affect how people value others, but awareness can help reduce unequal treatment.
Explanation:
The main point discussed in the narrative is an experiment called "the trolley problem" which, ultimately, aims to discover the hidden biases of people; where, in Tiffany's experiment, these people are represented by her 300 research participants. Though her findings seem to support that people value another person's lives differently, based on attractiveness, wealth, as well as disability; she concluded that being aware of these biases help with understanding where they are coming from and creating a more equal society by preventing it from happening.