Which law allows the Coast Guard to perform duties related to customs laws?

The correct choice is rooted in the provisions set forth by 19 USC 1401, which provides the legal framework for customs laws and regulations in the United States. This statute outlines the definitions and general provisions applicable to customs, directly linking the Coast Guard's authority to enforce customs regulations. Under this law, the Coast Guard has the jurisdiction to interdict vessels suspected of violating customs laws, making it essential for trade and border protection.

The other options listed have different contexts and applications. For instance, 14 USC 143 pertains to the Coast Guard's rescue and law enforcement missions, while 19 USC 1581 deals with the inspection and search of vessels, focusing more narrowly on enforcement. 14 USC 95 addresses the authority of the Coast Guard but is less explicitly related to customs enforcement duties. Each of these serves important functions within the Coast Guard's broader mission but does not provide the same primary foundation for customs law enforcement as the selected answer.