Final answer:
The last step in closing a public corporation's books for an accounting cycle is to sum up the columns for Exports, Imports and Balance to determine the final current account balance.
Step-by-step explanation:
The last step that must be taken before a public corporation’s books can be closed for an accounting cycle involves summing up the columns for Exports, Imports, and Balance within the financial records. This process determines the final current account balance. This number is crucial as it reflects the company’s trade balance and will be recorded as the closing balance for the accounting period. Ensuring the accuracy of this step is essential for providing a clear financial statement that can be used for analysis, reporting, and future planning.