## Core Concept
The phallic or Oedipal stage, a concept in Sigmund Freud's psychosexual development theory, is a critical period where children develop feelings for the opposite-sex parent and rivalry with the same-sex parent. This stage is characterized by the child's awareness of their genitals and the realization of anatomical sex differences.

## Why the Correct Answer is Right
The phallic stage, according to Freud, occurs approximately between the ages of 3 and 6. During this period, children become aware of their genitals and begin to understand the differences between boys and girls. This stage is marked by the Oedipus complex, where children supposedly desire the opposite-sex parent and feel jealousy towards the same-sex parent. This stage is crucial for Freud as it lays the foundation for future psychological development, including the resolution of the Oedipus complex through repression, which Freud believed was essential for the development of the superego.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is incorrect because it does not specify an age range but is not provided.
- **Option B:** This option suggests an age range that does not correspond with Freud's psychosexual stages.
- **Option D:** This option suggests a broader or different age range not associated with the phallic/Oedipal stage.

## Clinical Pearl / High-Yield Fact
A key point to remember is that Freud's psychosexual stages, including the phallic stage, are foundational to understanding psychoanalytic theory. The phallic stage, occurring between ages 3 and 6, is particularly notable for the Oedipus complex. Clinicians should be aware of these theoretical underpinnings, even if they do not subscribe to all aspects of Freud's theories, as they continue to influence contemporary psychology and psychiatry.

**Correct Answer: C. 3-6 years.**