According to Oracle documentation, when there is a business requirement for a subsidiary company to report to the parent company on a monthly basis with different currencies and no requirement to have daily balances, you should recommend Balance level as the data conversion level. A Balance level data conversion level enables you to translate balances from one currency to another at month-end or quarter-end for reporting purposes. A Balance level data conversion level minimizes the data stored in the reporting currency because it does not store daily balances or journal details. Therefore, option D is correct. Option A is incorrect because a Subledger level data conversion level stores daily balances and journal details in the reporting currency. Option B is incorrect because a Journal Level data conversion level stores journal details in the reporting currency. Option C is incorrect because an Adjustment only level data conversion level does not translate balances from one currency to another. Option E is incorrect because a Spreadsheet level data conversion level does not exist.