Answer: D. Human psychology.
Humanism as a school of thought sought to bring to the spotlight the system of thought that supported a person’s ability to make decisions based on their own freewill, and not as a result of predestination.
This school of thought stressed the importance of dignity and human values. It also proposed that people use science and reason to solve their problems.
When humanism spread into the literary world, authors and dramatists began writing about human psychology. This popularized the notion that man had to understand and appreciate their need for self-worth, personal happiness, freedom, etc.
At this time, the focus of literary works shifted from the religious, predetermined nature to man as self. It viewed man as an individual and social agent, and emphasized on aspects that provoked thoughts on philosophical, existential and moral truth-seeking.
The school of thought was quite unpopular because it excluded theocentrism.