What type of government is characterized by military leaders ruling after a coup?

A government characterized by military leaders ruling after a coup is known as a junta. This term refers specifically to a situation where a small group of military officers takes control of the government, often following the overthrow of an existing regime. Junta leaders typically assume power without following traditional constitutional processes and may maintain control through military force or intimidation.

The context surrounding a junta often involves instability and the suspension of civilian rule, which distinguishes it from other forms of governance like oligarchies, where power is held by a few elite individuals or groups, or autocracies, where one individual holds absolute power. Monarchies, by contrast, are systems where sovereignty is held by a single ruler, often inherited. In summary, a junta is specifically identified by its military composition and seizure of power, making it the correct answer.