What should be done immediately if a candidate notices an issue in the testing procedure?

When a candidate notices an issue in the testing procedure, the most appropriate action is to report it to the invigilator. This is crucial because the invigilator is responsible for maintaining the integrity of the exam environment, ensuring that all candidates have a fair testing experience. Timely communication with the invigilator allows any potential problems to be addressed immediately, thereby minimizing any potential impact on all candidates involved.

Other options, such as waiting until the test is over or informing only friends, do not facilitate any resolution of the issue and could compromise the testing integrity for everyone. Writing down feedback may seem helpful, but it does not address the issue in the moment and delays potential corrective action. Acting promptly by reporting the concern ensures that appropriate measures can be taken during the exam.