The correct answer is the phallic stage.
According to Freud's theory of psychosexual development, children aged 3-6 years old are in the phallic stage of psychosexual development. During this stage, the primary focus is on genitals and libido. Boys go through something called the Oedipus Complex, where they envy their father and want to replace them so they get their mother's sole attention and love. Girls on the other hand go through the Electra Complex where they want to possess their father.