What technique involves interposing goods or services to disguise their true nature?

The technique that involves interposing goods or services to disguise their true nature is known as commingling of goods. This practice typically occurs in situations where individuals or businesses blend legitimate goods with illicit items in order to obscure their illegal nature. By mixing these goods, it becomes difficult for authorities to trace the origins or the intended purpose of the hidden illicit items.

Commingling serves to create a façade of legality surrounding the operation, making it challenging for law enforcement to investigate and identify contraband or illegal activities. This method can be particularly deceptive and is often used in export and import operations to evade customs scrutiny.

In contrast, the other options represent different techniques or practices that, while potentially involved in illicit activities, do not specifically pertain to the act of disguising the nature of goods through intermingling. For example, double invoicing typically involves providing false invoices to misrepresent costs or transactions for financial gain, controlled delivery refers to the monitoring of an illegal shipment by law enforcement to catch offenders in the act, and undeclared transactions involve failing to report certain transactions to evade taxes or restrictions without necessarily obscuring the nature of goods through mixing.