Which of the following is an example of a constitutional power?

The power to make laws regarding trade is a constitutional power because it is explicitly granted by the Constitution, specifically under the Commerce Clause. This clause allows the federal government to regulate commerce with foreign nations, among the several states, and with Indigenous tribes. This power is foundational to federal authority, enabling the government to create laws that can help maintain a coherent economic framework across state lines and facilitate international trade.

In contrast, local ordinances are typically enforced by local governments and do not have constitutional backing at the federal level; thus they derive from state constitutions or local laws. The power to impose taxes on income can vary, as both state and federal governments have this capability, but the specifics and limitations can be found in statutory law rather than directly in the Constitution. Collecting fees for licenses usually falls under state or local governance and does not stem from a constitutional directive but rather from the powers granted to those local authorities to regulate their own affairs. Each of these latter powers, while significant, does not represent the specifically delineated powers found in the Constitution itself as does the power to regulate trade.