Final answer:
Whistleblowing is the most effective tool listed for uncovering unethical or illegal activities in an organization, with financial audits also being significant. Whistleblowers are protected by various acts that encourage reporting of wrongdoing without the risk of retaliation.
Step-by-step explanation:
Among the options listed, whistleblowing appears to be the most effective tool for uncovering unethical or illegal activity in an organization. Whistleblowing involves reporting such activities to the authorities or the public, usually by someone within the organization. It has been recognized as a crucial component in maintaining organizational accountability. The importance of whistleblowing is evidenced by legislation such as the Civil Service Reform Act of 1978, the Whistleblower Protection Act of 1989, and the Whistleblower Protection Enhancement Act of 2012, which have provided protections from retaliation for those who come forward to report wrongdoing. Financial audits also play a significant role in detecting irregularities in an organization's finances, which can be indicative of illegal activities. While performance evaluation and employee training are important aspects of an organization's oversight and improvement strategies, they are more focused on improving and maintaining productivity and not specifically designed to uncover illicit behaviors.