**Core Concept**
Freud's psychosexual theory proposes that human development is influenced by the interaction between the child's biological and psychological needs, leading to the development of personality and character traits. This theory is divided into several stages, each corresponding to a specific age range and oral, anal, phallic, latent, and genital stages.

**Why the Correct Answer is Right**
During the phallic stage (approximately 3-6 years), children experience a surge in libidinal energy and begin to focus on their genitals. The development of mixed dentition (a mix of primary and permanent teeth) typically occurs around this age, as the primary teeth start to fall out and are replaced by permanent teeth. Furthermore, character formation is also a significant aspect of this stage, as children begin to develop a sense of identity and learn to navigate social relationships. The phallic stage is marked by the Oedipus complex, where children develop feelings of desire for the opposite-sex parent and rivalry with the same-sex parent.

**Why Each Wrong Option is Incorrect**
**Option A:** The oral stage (0-1.5 years) is characterized by the development of sucking and feeding habits, not the development of mixed dentition or character formation.
**Option B:** The anal stage (1.5-3 years) is associated with the development of bowel habits and toilet training, not mixed dentition or character formation.
**Option C:** The latent stage (6-12 years) is a period of relative calm in psychosexual development, during which children begin to repress their libidinal energy and focus on social and academic development, rather than the development of mixed dentition or character formation.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that Freud's psychosexual theory is a developmental framework that helps explain the formation of personality and character traits. While it may seem unrelated to clinical practice, understanding the stages of psychosexual development can provide insight into adult psychological dynamics and help clinicians develop more effective therapeutic relationships.

**Correct Answer: C. Phallic stage.**