According to Sigmund Freud, the three systems of the human psyche that regulate the libido are the:

A) personal unconscious, collective unconscious, and archetypes.
B) id, ego, and superego.
C) ego, unconscious, and subconscious.
D) aggressive drive, id, and the superego.

According to Freud's psychoanalytic theory, the id is the primitive, instinctual part of the psyche that is driven by the pleasure principle, the ego is the rational, logical part of the psyche that mediates between the id and external reality, and the superego represents internalized ideals, morals, and values. These three systems work together to regulate the libido, or psychic energy, that drives human behavior.