Attempts at scientifically validating Freudian concepts indicate that

A) not one of Freud's ideas has scientific support.
B) almost all of Freud's ideas have scientific support.
C) there is scientific support for some of Freud's ideas but not for others.
D) Freudian ideas cannot be investigated scientifically.

While some of Freud's ideas, such as the existence of the unconscious and the importance of early childhood experiences, have empirical support, others, such as the Oedipus complex and the idea of the death drive, have not been substantiated by scientific evidence. Therefore, there is scientific support for some of Freud's ideas but not for others.