What test does the Reverend Mother of the Bene Gesserit force Paul Atreides to take?

What test does the Reverend Mother force Paul Atreides to take? She forces Paul to undergo the Gom Jabbar test, a deadly Bene Gesserit trial of self-control and humanity.

Reverend Mother Gaius Helen Mohiam places Paul’s hand inside a pain-inducing box while holding the Gom Jabbar, a poison-tipped needle, against his neck. Paul must resist the instinct to withdraw his hand. If he moves, Mohiam will kill him immediately. The test is designed to distinguish a reasoning human from an animal ruled entirely by instinct.

Paul’s ability to endure the pain impresses Mohiam and confirms that he possesses unusual mental and physical discipline. The scene also introduces the Bene Gesserit’s long-term interest in Paul as a possible Kwisatz Haderach, the male figure their breeding program seeks to produce.

The Gom Jabbar is often mistaken for the box itself, but the terms refer to different parts of the ordeal: the box causes the pain, while the Gom Jabbar is the poisoned needle used to enforce obedience.