Read the passage from "When Good People Do Bad Things,” which is an informational text about research into group behaviors. In a study that recently went online in the journal Neurolmage, the researchers measured brain activity in a part of the brain involved in thinking about oneself. They found that in some people, this activity was reduced when the subjects participated in a competition as part of a group, compared with when they competed as individuals. Those people were more likely to harm their competitors than people who did not exhibit this decreased brain activity.

What is the author’s most likely purpose for writing this particular passage?

a. to explain possible causes of harmful group behavior
b. to suggest solutions for reducing harmful group behavior
c. to explain reasons for decreased brain activity
d. to suggest solutions for decreased brain activity