Why Is the Antidepressant Medication Lithium Also Referred to as a Mood

Why is the antidepressant medication lithium also referred to as a mood stabilizer?

A) because it increases the availability of both dopamine and norepinephrine in the brain
B) because it increases thyroid functioning, which results in improved mood stabilization
C) because it helps to prevent manic episodes
D) because it elevates serotonin levels, which prevents depression