Which of the following is a weakness of the cash basis accounting method?

The cash basis accounting method has the primary weakness of not matching revenues with expenses. This method records revenue when cash is received and expenses when cash is paid, which can create timing discrepancies. As a result, this method may not accurately reflect the financial performance of a business at any given time, particularly in periods where there are significant receivables or payables outstanding. In contrast, accrual accounting more accurately matches revenues with the related expenses in the period in which they occur, providing a clearer picture of financial performance.

The other choices highlight features or characteristics of cash basis accounting rather than weaknesses. It may accurately reflect a business's cash flow at a certain moment (denoted in the first option), may be perceived as simple and easy to use (in the third), and it is not necessarily burdensome in terms of record-keeping when compared to other methods like accrual accounting. Thus, the significant drawback of the cash basis method is indeed its failure to align revenues and expenses, which can lead to misleading financial statements.