Final answer:
To prevent potential fraud by an accountant, implementing Job rotation is the best solution. Job rotation provides a way to periodically introduce a new set of eyes to the accounting books, which can help identify irregularities and deter fraudulent behavior.
Step-by-step explanation:
If you are concerned that an accountant in your organization might have the opportunity to modify the books and potentially steal from the company, the best solution to implement would be C) Job rotation. Job rotation involves periodically moving employees to different tasks and responsibilities. In the context of preventing fraud, this means having another person take over all accounting tasks at certain intervals. The fresh set of eyes can help identify and catch any irregularities that may have occurred. This practice can deter fraudulent behavior by making it more difficult for an individual to conceal their actions over an extended period.
Two-factor authentication is more about securing access to systems rather than auditing processes, VPN (Virtual Private Network) is mostly about secure remote access, and a firewall is aimed at protecting systems from external threats or unauthorized access, none of which directly address the internal checks and balances needed to prevent fraud within accounting practices.