The source of a government's authority to make and enforce decisions primarily depends on:

The correct option is

The nature of the political system

Explanation

The legitimacy and source of a government's power are fundamentally determined by the form or type of government established in a country. Different political systems derive their authority from different sources, such as the will of the people, hereditary rights, or military force.

Option-wise Analysis

• The written Constitution is Incorrect: While a written Constitution is the source of authority in constitutional democracies (like India or the USA), not all governments possess a written constitution (e.g., the United Kingdom has an unwritten constitution). Furthermore, in absolute monarchies or dictatorships, the constitution may not be the true source of power.
• The military strength is Incorrect: Military strength is the primary source of authority in a military dictatorship or authoritarian regime. However, in democratic systems, the military is subordinate to the civil political authority and is not the source of the government's power to make decisions.
• The nature of the political system is Correct: The nature of the political system is the determining factor.
  • In a Democracy, the authority comes from the people (popular sovereignty), exercised through elections and defined by a constitution.
  • In a Monarchy, the authority is often derived from tradition, heredity, or "divine right."
  • In a Dictatorship, the authority is derived from force or control over the state apparatus.
  Therefore, the specific source of power depends entirely on which political system is in place.
• The international community is Incorrect: The international community provides external recognition (sovereignty in international law) but is not the internal source of authority for a government to make and enforce domestic laws.

Key Takeaway: The source of a government's authority is not universal; it is contingent upon the type of government (Democracy, Monarchy, etc.). In a democracy, this authority flows from the people, whereas in other systems, it may flow from lineage or force.