Explanation:

- In this scenario, A tries to pull Z's nose. Z, in self-defense, holds A to protect himself.

- A, in a fit of sudden and violent passion caused by Z’s defense, kills Z.

- The crucial point is whether A's act falls under "murder" or a lesser offense, like "culpable homicide."

- According to Indian Penal Code, killing someone in response to a minor provocation (like being held back for pulling a nose) is not considered grave and sudden enough to lose the benefit of lesser culpability.

- Therefore, the killing here is not murder because the provocation was not grave; it is considered culpable homicide not amounting to murder under Exception 1 to Section 300 IPC.

- Option 1: Murder – Not correct, as the provocation was not grave.

- Option 2: Abetment of murder – Not relevant; Z did not abet the killing.

- Option 3: Culpable homicide – Correct answer. Killing under sudden passion without grave and sufficient provocation typically falls here.

- Option 4: Grievous hurt – Not correct as it resulted in death.

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