Supervisory Oversight in Ethical Duties

In the context of the CFA Institute Code of Ethics and Standards of Professional Conduct, particularly concerning an investment firm's obligation to supervise its employees, consider the following scenario:

John, a portfolio manager at Alpha Investments, has been working on a high-stakes project that could significantly influence the firm's reputation and market position. His immediate supervisor, Lisa, is aware of John's extensive workload and has emphasized the importance of deadlines. However, Lisa has not provided John with sufficient guidance on firm policies regarding personal trading, which leads to John's oversight in executing his trades.

As John makes a substantial personal trade that coincides with his clients' portfolios, the firm faces potential allegations of insider trading. Which of the following represents Lisa's failure in her supervisory role according to the CFA Institute Standards?