What is a project risk mitigation step a test manager might take?

A project risk mitigation step refers to actions taken to reduce the probability or impact of potential risks that could negatively affect the project. In the context of the choices provided, arranging a back-up test environment in case the current one fails is a proactive measure that directly addresses a specific risk associated with resource availability and system reliability during testing.

By having a back-up test environment, the test manager ensures that testing can continue uninterrupted, safeguarding the project timeline and preventing delays caused by environment failures. This is essential in maintaining the continuity of the testing process and ensuring that quality is upheld throughout the project.

The other options, while relevant to various aspects of testing and project management, do not serve as direct risk mitigation steps in the same way. For instance, testing for performance problems is a standard part of testing but does not specifically mitigate a risk; hiring a contractor after a test analyst leaves is a reactive measure and does not prevent the risk of staff turnover; and performing a project retrospective meeting is a valuable practice for lessons learned but does not address specific risks proactively. Thus, the focus on creating a reliable back-up system is what makes it the most effective risk mitigation step among the choices.