Under the Bank Secrecy Act, a Currency Transaction Report (CTR) must be filed when a customer conducts a cash transaction exceeding what threshold in a single business day?

Correct answer: $10,000

The Bank Secrecy Act requires financial institutions to file a Currency Transaction Report (CTR) for any cash transaction exceeding $10,000 in a single business day. This includes multiple transactions by the same person that total more than $10,000. "$7,500" ($5,000) is a threshold associated with certain money services businesses for other reporting, not CTRs. "$25,000" ($7,500) is not a standard BSA threshold. "$10,000" ($25,000) exceeds the actual CTR requirement and would result in underreporting.