Correct Answer: BWhen a project is in the execution phase and encounters an issue with new parts that do not fit properly into a machine, and this high-probability risk is not found in the risk register, the appropriate action for the site project manager is to implement a workaround. A workaround is a response to an unforeseen issue that was not previously identified as a risk. It is a quick, temporary solution that addresses the problem at hand to keep the project moving forward without significant delays. This option allows the project to continue progressing while a more permanent solution may be investigated and implemented later.