Which of the following actions can the Coast Guard perform under its authority?

The option that highlights the Coast Guard's authority to make inquiries and perform inspections is particularly pertinent because it underscores one of the primary roles of the Coast Guard in national security and maritime law enforcement. As a maritime enforcement agency, the Coast Guard is tasked with ensuring compliance with various laws and regulations, especially those related to safety, security, and environmental protection.

By conducting inquiries, the Coast Guard can gather information regarding the operations and status of vessels and individuals, which is essential in carrying out their mission effectively. Performing inspections allows the Coast Guard to assess compliance with safety standards, licensing requirements, and other regulatory measures, ensuring that vessels meet the necessary criteria to operate safely and legally.

This authority is crucial, especially in contexts such as preventing illegal activities (like smuggling or human trafficking), enforcing environmental laws, and ensuring the safety of navigation. In contrast, the other options listed do not accurately reflect the responsibilities granted to the Coast Guard. The agency does not have the authority to check on domestic transportation services, detain individuals without legal justification, or impose taxation. Therefore, the ability to make inquiries and perform inspections aligns perfectly with the operational and enforcement objectives of the Coast Guard.