Alittle boy reverts to the oral comfort of thumb sucking on the way to his first day of school. what defense mechanism is he using? rationalization reaction formation regression projection

A little boy reverts to the oral comfort of thumb sucking on the way to his first day of school. He is using regression defense mechanism. Regression occurs where a person returns to a child state to escape the present. It is a defense mechanism leading to the temporary or long-term reversion of the ego to an earlier stage of development

25 ) where the jellyfish were counted at