Which of the following is NOT a characteristic of concurrent powers?

Concurrent powers are those that are shared by both the federal and state governments. Examples of concurrent powers include activities that both levels of government can perform simultaneously, such as levying taxes, establishing public schools, and borrowing money. Each of these powers plays an essential role in governance at various levels, allowing for a shared responsibility in managing resources and serving the populace.

Conducting foreign relations, however, is a power that is reserved for the federal government. It is exclusively managed at the national level, as it involves diplomacy, international treaties, and various interactions with other nations. States are not permitted to conduct foreign relations independently, which differentiates it from the other options listed. Thus, the correct answer identifies the activity that does not fall under the category of concurrent powers.