Final answer:
To stop a suspicious application with high CPU usage, right-click on it in Task Manager and select 'End task' to terminate the process and free up resources.
Step-by-step explanation:
If Bryce's computer is experiencing high CPU utilization due to a suspicious application, and you are looking to stop that application using Task Manager, the correct action to take would be to terminate the process. Once you have identified the application using a high percentage of the CPU in Task Manager, you should right-click on the process and select End task. This will forcefully close the application and should release the CPU resources that it was consuming, which can lead to an improvement in the computer's overall performance.