According to the statement provided, which type of transactions requires disclosure?

Off balance sheet transactions require disclosure because they represent financial arrangements or obligations not recorded directly on the balance sheet. These transactions can significantly affect a company's financial position and performance, providing investors and creditors with vital information about actual financial risks or commitments. Disclosing off balance sheet transactions allows stakeholders to have a more comprehensive understanding of the company’s financial health and obligations, ensuring transparency and informed decision-making.

In contrast, while foreign currency transactions, inventory valuation methods, and cash flow estimates are relevant to financial reporting, they do not inherently require the same level of disclosure as off balance sheet transactions. For instance, foreign currency transactions are typically included in financial statements but are accounted for under established policies. Inventory valuation methods, while important for proper accounting practices, usually appear in the notes to the financial statements without the same urgency for disclosure as off balance sheet items. Cash flow estimates are often part of supplementary disclosures, but the specifics of off balance sheet transactions can have far-reaching implications that warrant explicit disclosure to give a fuller picture of a company's financial obligations.