Apollonia Was Diagnosed with Major Depressive Disorder Five Years Ago

Apollonia was diagnosed with major depressive disorder five years ago. She knows her mother took medicine to combat depression and she worries her daughter will experience depression too. Why?

A) Apollonia also suffers from social anxiety disorder.
B) Mood disorders are more likely to occur in younger people.
C) Mood disorders have been shown to have a strong genetic and biological basis.
D) People who grow up with a depressed parent usually become depressed themselves.