Question

In Erikson's ________ stage of psychosocial development, preschoolers are challenged to control their own behavior

Answer 1

That would be Stage 3, which Erikson called "Initiative vs. Guilt."

This is the stage where children start making their own decisions. It's the beginning of their self-confidence.
They'll plan games and activities to play with other children. They'll become more assertive, and more forthcoming with their desires. They'll ask lots and lots of questions.
They'll take the "initiative."

Parents play an important role in this stage of development (like all other stages), because this is the stage where children can actually start behaving recklessly.
They might become disobedient.
They might cross the street without an adult.
They might wander off and talk to random strangers.

And parents do need to step in, and reprimand children, whenever they do something that is reckless or potentially harmful.

And when children are reprimanded, they feel guilt (which is why this stage is called "initiative vs. guilt").

And with this guilt, children are challenged to control their behavior. With some practical parenting, children can learn how to inhibit behaviors that are harmful, while continuing to develop their self confidence through initiative, and interaction with other children.