The correct answer to the question is option 1 - an aircraft carrier. INS Vikramaditya is the name given to an aircraft carrier that is scheduled to be inducted into the Indian Navy in the near future.

An aircraft carrier is a large naval vessel that is primarily used for the operation and deployment of military aircraft. It has a large flight deck that allows for the takeoff and landing of aircraft, and it typically carries a mix of fighter planes, helicopters, and other support aircraft.

Option 2 - a nuclear submarine, refers to a different type of naval vessel. A nuclear submarine is a submarine powered by a nuclear reactor, and it is primarily used for underwater operations.

Option 3 - an amphibious assault vessel, also known as a landing ship, is a type of naval vessel designed to transport and land troops, vehicles, and equipment onto a beach during amphibious operations.

Option 4 - a stealth ship, refers to a type of naval vessel that is designed to have a low radar signature and is difficult to detect using conventional radar systems.

Therefore, the correct answer to the question is option 1 - an aircraft carrier.