Which of the following is not a denomination of currency listed in the selling money to vault?

The correct answer is "Ace" because it is not a denomination of currency in the context of selling money to a vault. Denominations refer specifically to the different values of currency that are issued, which include various amounts like 20, 50, and 100. These values represent fixed monetary units that can be found in banknotes and coins.

In contrast, "Ace" typically refers to a playing card, which has no relevance in banking or currency denominations. The term has no association with actual currency, making it the clear choice for the option that does not belong among the listed denominations of currency for banking transactions. Understanding currency denominations is crucial for bank tellers, as they must accurately identify and manage different forms of currency during transactions.