Explanation:

This question addresses the general exceptions to criminal liability under the Indian Penal Code (IPC), specifically concerning acts done under the authority of law. The act of a hangman executing a death sentence is a classic example of such an exception. **Analysis of Options:** * **Option (1) Section 77 of I.P.C.:** Section 77 of the IPC deals with the 'Act of Judge when acting judicially'. It states that nothing is an offence which is done by a Judge when acting judicially in the exercise of any power which is, or which in good faith he believes to be, given to him by law. This section protects judges for their judicial acts, not individuals carrying out court orders. Therefore, this option is incorrect. * **Option (2) Section 78 of I.P.C.:** This is the correct answer. Section 78 of the IPC is titled 'Act done pursuant to the judgment or order of Court'. It states: "Nothing which is done in pursuance of, or which is warranted by the judgment or order of, a Court of Justice; if done whilst such judgment or order remains in force, is an offence, notwithstanding that the Court may have had no jurisdiction to pass such judgment or order, provided the person doing the act in good faith believes that the Court had such jurisdiction." The hangman's act of executing a prisoner is directly in pursuance of a judgment and order of a Court of Justice. The hangman is merely an instrument of the law, carrying out a lawful command. As long as the court's order is in force, the hangman is protected from criminal liability for performing this duty. This section ensures that individuals who are legally bound to execute court orders are not held criminally responsible for acts that would otherwise be offenses. * **Option (3) Section 79 of I.P.C.:** Section 79 of the IPC deals with 'Act done by a person justified, or by mistake of fact believing himself justified, by law'. This section protects individuals who, by reason of a mistake of fact and not by reason of a mistake of law, in good faith believe themselves to be justified by law in doing an act. Examples include a person arresting a thief whom he believes to be a police officer. This is about acting under a belief of legal justification, not directly executing a court order. Therefore, this option is incorrect. * **Option (4) Section 76 of I.P.C.:** Section 76 of the IPC deals with 'Act done by a person bound, or by mistake of fact believing himself bound, by law'. It states that nothing is an offence which is done by a person who is, or who by reason of a mistake of fact and not by reason of a mistake of law in good faith believes himself to be, bound by law to do it. An example is a soldier firing on a mob in obedience to the orders of his superior officer, which are in conformity with the law. While a hangman is bound by law, Section 78 is more specific to acts done *pursuant to a court's judgment or order*, making it the more precise and applicable provision. Section 76 is a broader provision. Therefore, while related, Section 78 is the more accurate answer. Therefore, the hangman is exempted from criminal liability under Section 78 of the IPC because he is merely executing a lawful judgment or order of a Court of Justice.