Answer: Deposit run-off.

**Deposit run-off** is generally considered the largest threat to a bank's liquidity because: - Deposits represent a significant portion of a bank's funding base - Retail deposits can be withdrawn rapidly and simultaneously by many customers - This creates immediate cash outflow pressure - Unlike wholesale funding, retail deposits are typically unsecured and can be withdrawn without notice - Historical banking crises often feature deposit runs as a primary trigger While loss of wholesale funding and secured funding are significant threats, deposit run-off typically poses the most immediate and widespread liquidity risk due to its scale and speed.

Author: LeetQuiz .