The Commerce Clause gives the Federal Government a wide array of powers, because so many things concern business that happens across state lines. The ability to do business is greatly dependent upon whether people have access to the things required to participate in business activities, particularly those that are disabled. By ensuring that people with disabilities have many of the same opportunities as those without disabilities the government is able to ensure that all people, regardless of what state they are in, have equal opportunity within the business world. The ability to regulate commerce between the states allowed Congress to step-in and pass this landmark law.

While the Supreme Court has acted quite a few times to loosen its reins over the federal government and its management of commercial activity, the Great Depression was, by far, the most decisive prompting event for the Court. When President Franklin D. Roosevelt began to pass various wide-ranging economic and welfare laws as part of his New Deal, which was intended to slow down the Depression’s ravages on ordinary citizens, the Court was at first suspicious and hostile. But by 1937, the Court had seen the wisdom in the President’s New Deal and over the course of the next several years, the Court relaxed the commercial constraints it had once placed upon the federal government, thereby allowing the President and Congress to take broad action to shore up the struggling economy, to relieve poverty, and to create job opportunities across the nation. This trend continued for several decades, but more recently, the Court has slowly begun to reverse itself and has started to revoke some of these more expansive permissions, to the pleasure of the states.

Advocates of states’ rights, as well as other individuals concerned with placing constraints upon the national government, most often cite the Tenth Amendment as the Constitution’s most powerful defense of the powers of state governments. According to the Tenth Amendment, any and all powers that the Constitution does not expressly grant to the federal government – and which are not conversely banned from state usage – “are reserved to the states respectively.” In other words, this leaves many powers not clearly described in the Constitution available to the states – in theory. In actuality, the Supreme Court has customarily disagreed; throughout the long history of disputes over power and control between the states and the federal government, the Supreme Court has most often proclaimed the federal government to be the victor. According to the Supreme Court (and other pro-national government advocates), the Tenth Amendment is trumped by the Supremacy Clause. Contained in Article IV of the Constitution, the Supremacy Clause states that any laws and treaties passed in Washington, D.C. automatically overrule any state laws (just as long as the national government’s actions fall within the Constitution’s purview, of course). The Supremacy Clause sets the Constitution up as the supreme law of the land, with the federal government as the document’s most empowered enforcer. Yet this has not stopped state governments from challenging federal actions and each victory for a state has often emboldened the others.

The Supreme Court of the United States stands distinct from the other branches of government. It was created with the intent of being independent and free of political influence to enable it to rule clearly on the cases brought before it without any prejudgment or belief. While several of the answer options may seem logical, they imply a close relationship between the the Supreme Court and the Executive and Legislative Branch that is not included in the Constitution.  

Minority rights is a principle that even in a democracy ruled by majority voting, those people who are not members of the majority in belief, ethnicity, or cultural backgorund should not be shut out of the democratic process. While this is usually quite difficult to achieve, one method that can help is by creating congressional districts that are built around certain constituencies so as to insure they have representation.

"First past the post" describes a system in which elections are won by the candidate with the most votes. This is in contrast to systems where, for example, numbers of representatives are elected proportional to the share of the votes their party received. Students who know this can ignore answers that are fundamentally at odds with the American governmental system, such as the "requires nonpartisanship" and "ambiguous electoral results" answers. Then, it becomes a matter of striking out answers which are not necessarily restricted to this type of electoral system ("low voter turnout" and "electoral fraud"). This leaves us with the correct answer, marginalizing third parties.

Alternately, students can contrast the American electoral system with say, the British system of proportionate representation and find key contrasts, e.g. the relative scarcity vs. abundance of third parties.

Direct Democracy refers to a system of government in which citizens directly vote on issues and the majority prevails. This is impractical on a national level, where there are millions of would-be voters, so a representative democracy, or a republic, is established where representatives are elected to "represent" the voting interests of the people.

While many Constitutionally-related changes have occurred over the span of American history, the most widespread and vital transformation has been the various expansions of democracy that have taken place. The abolition of slavery, suffrage for both African Americans and women, the lowering of the national voting age (to eighteen), the passage of civil rights legislation, and the direct election of Senators are just some of the most crucial ways in which more and more American citizens have gained increased democratic rights, influences, and freedoms. This Together with the nation and its people, the Constitution has continually evolved along these lines, often through the passage of relevant amendments (such as the Fifteenth Amendment which banned racial discrimination and the Nineteenth Amendment’s grant of voting rights to women). Further democratic expansions and changes are sure to come.

Pluralism often describes modern American society, especially since the 1960s. Pluralism is used in discussions of politics to refer to a society in which many different groups with many different opinions and viewpoints all have to coexist and work with each other in the political sphere. This stands in stark contrast to the popular view in the early twentieth century which held that whatever the majority of people believed should govern society.

The 13th Amendment to the United States Constitution states, "Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction." Therefore, the 13th Amendment is the correct answer.