A return to behavior characteristic of earlier stages of development is called ______.

A) regression
B) reduction
C) nostalgia
D) melancholia

Regression

In statistics, a method for modeling the relationships between one or more independent variables and a dependent variable; in psychology, a defense mechanism leading to the temporary or long-term reversion of the ego to an earlier developmental stage rather than handling unacceptable impulses in a more adult way.

Reduction

The process of simplifying or breaking down complex entities into simpler components, often used in scientific and mathematical problem-solving.

Nostalgia

A sentimental longing or wistful affection for the past, typically for a period or place with happy personal associations.