Explanation:

- Assault: This involves causing someone to fear imminent physical harm. It doesn’t apply here since Z was killed.

- Culpable Homicide: This is a broader term that includes unlawful killing without specific intent to kill, often resembling manslaughter in some jurisdictions.

- Murder: This is the intentional and unlawful killing of another person with premeditation. A had the intention to kill Z, and succeeded, which fulfills the criteria for murder.

- Criminal Use of Force: This generally refers to using force in an unlawful manner but doesn’t specifically focus on causing death.

Murder is the correct choice because A intended and succeeded in killing Z.