Why is making only one change at a time useful during troubleshooting?

Correct answer: It becomes easier to identify the actual cause of the problem

Changing one setting, cable, driver, or component at a time follows a controlled troubleshooting method. If the problem disappears after that single change, the technician can reasonably connect the result with the change and record what solved it. Multiple changes made together hide cause-and-effect relationships and may create new problems. Thus option B is correct; the other choices describe effects unrelated to systematic diagnosis.