Which of the following statement best describes the understanding with respect toownership and custody of working papers prepared by an auditor?

• A. The working papers may be obtained by third parties when they appear to be relevant to issues raised in litigation
• B. The safe custody of working papers is the responsibility of client, if kept at his premises
• C. The working papers must be retained by an audit firm for a period of 10 years
• D. Successor auditors may have access to working papers of the predecessor auditors. The approval of client is not required.