Final answer:
The MAX(VendorName) aggregate expression finds the VendorName that's last in alphabetical order, acting as the maximum value in text-based sorting.
Step-by-step explanation:
The aggregate expression that finds the VendorName column that's last in alphabetical order is a. MAX(VendorName). This is because the MAX() function in SQL and other database languages is used to find the maximum value in a column, and when used with text columns, it returns the highest value according to the alphabetical order. Therefore, the MAX() function would return the last name if sorting alphabetically.