Which of the following is the most reliable evidence for testing employee access to a financial system?

The most reliable evidence for testing employee access to a financial system is a list of accounts with access levels generated by the system. This option is based on the direct output from the financial system itself, which provides an accurate and up-to-date reflection of who has access and what level of access they possess. This type of documentation is typically generated automatically by the system and is less prone to human error or manipulation than other forms of evidence.

A generated list can be used to cross-reference with the expected access rights based on the organization's policies and employee roles, making it an effective tool for audits and access reviews. It presents a clear-cut, factual representation of access controls that can be independently verified, ensuring that the information is both current and comprehensive.

In contrast, other options like spreadsheets provided by the system administrator or human resources access documents could be subject to inaccuracies or changes that are not documented accurately in real-time. Observations performed onsite, while valuable for a practical assessment, may only capture a snapshot in time and do not provide ongoing evidence of access levels, making them less reliable as a definitive source of access validation.