Which of the following refers to a sale where controlled substances are sold in minimal amounts without specific prescription requirements?

The term that refers to a sale where controlled substances are sold in minimal amounts without specific prescription requirements is known as a "causal sale." This type of sale typically allows for the distribution of small quantities of controlled substances without needing to adhere to the stricter regulations associated with prescription medications.

In this context, the casual nature of the sale implies that the transactions are conducted informally or infrequently and do not require the same legal oversight as regular sales of controlled substances, which usually demand a prescription from a licensed healthcare professional.

The other options do not accurately describe this type of sale. An emergency sale is defined by particular criteria that require the immediate distribution of medications under urgent circumstances, following specific legal guidelines. An imported sale refers to substances being brought in from outside the country, which is heavily regulated, especially for controlled substances. Unregulated sale is a term that might imply a complete lack of control but doesn't specifically address the context of selling controlled substances in minimal amounts without prescription requirements.