Which of the following actions is the clearest example of domestic policy within a country rather than foreign policy?

Introduction / Context:
In civics and political science, a useful distinction is made between domestic policy and foreign policy. Domestic policy refers to decisions and laws that affect conditions inside a country, such as taxation, education, health, and environment. Foreign policy covers relations with other countries, including treaties, trade agreements, and diplomacy. This question asks which example best illustrates domestic policy.

Given Data / Assumptions:

• Domestic policy deals with internal matters such as taxes, social programmes, regulation, and rights within a country.
• Foreign policy deals with international relations, treaties, alliances, and war or peace with other countries.
• The options describe actions of courts, governors, presidents, legislatures, and foreign ministers.
• The task is to select the example that clearly concerns internal law and public policy rather than international relations or personal political decisions.

Concept / Approach:
The clearest example of domestic policy among the options is a law passed by the national legislature granting tax credits for installing solar panels. This is an internal measure that changes how citizens and businesses are taxed and encourages renewable energy within the country. While some other options involve internal institutions, they either focus on judicial review of a specific law that touches on imports or on personal political decisions rather than broad policy. Options that involve peace treaties or defence alliances clearly belong to foreign policy, not domestic policy.

Step-by-Step Solution:
Step 1: Identify which examples refer directly to policy measures that affect domestic economic or social conditions.Step 2: Recognise that passing a law to grant tax credits for installing solar panels changes domestic tax rules and promotes renewable energy within the country, which is a classic domestic policy action.Step 3: Observe that the Supreme Court striking down a law involves judicial review of legislation, which is a constitutional function rather than the formulation of policy itself.Step 4: Note that a governor deciding not to run for a second term is a personal political decision, not a policy choice.Step 5: See that negotiating a peace treaty or signing a defence alliance clearly concerns foreign policy and international relations.Step 6: Conclude that the tax credit law for solar panels is the most straightforward example of domestic policy.

Verification / Alternative check:
Political science textbooks define domestic policy as a set of decisions that government makes regarding internal affairs, including taxation, regulation, welfare, crime, and environmental protection. A law that introduces tax credits for solar panel installation fits this definition exactly. Foreign policy, by contrast, involves decisions about how to interact with other states. This classification confirms that the option involving tax credits for solar panels exemplifies domestic policy.

Why Other Options Are Wrong:
The Supreme Court striking down a law is an important constitutional act but it is more about judicial review than about creating a new domestic policy programme. A governor choosing not to run again is a political choice and does not create policy for citizens. The president negotiating a peace treaty and the foreign minister signing a defence alliance are both foreign policy actions because they involve relations with other sovereign countries. Therefore, they do not represent domestic policy in the sense used in the question.

Common Pitfalls:
Students sometimes confuse any governmental action with policy, even if it is a court decision or a personal decision by a politician. Others may be misled by references to imports and think that striking down a law related to imports is domestic policy. While the law itself may concern domestic regulation of trade, the example focuses on judicial action rather than the original policy measure. The safest and clearest answer is the example that shows the legislature actively designing an internal tax incentive programme.

Final Answer:
The national legislature passing a law that grants tax credits for installing solar panels is the clearest example of domestic policy.