PART A: Which statement identifies the central idea of the text?

A
Behaving in a truly altruistic manner is an important part of being human; the reasons why people do it are less important.
B
Psychologists are unable to agree if true altruism exists, but they believe several factors could be encouraging people to act in seemingly selfless ways.
C
Psychologists have determined that true altruism doesn’t exist because humans are compelled to always put themselves first.
D
Behaviors should be discussed in terms of their prosocial nature because psychologists still don’t fully understand the nature of altruism.
(from common lit)