Which Control Panel utility should a technician use to find a protected .dll file that is missing from the System32 directory?

The most suitable Control Panel utility to find a protected .dll file that is missing from the System32 directory is Folder Options. This utility directly relates to file management and visibility settings within Windows.

By accessing Folder Options, a technician can adjust settings related to the viewing of hidden and protected operating system files. The System32 directory contains critical system files, including protected .dll files that are typically hidden to prevent unintentional modifications or deletions.

By enabling the visibility of hidden files and system files through Folder Options, the technician can search more effectively for the specific .dll file in question.

This is particularly important because the other utilities mentioned do not provide the functionalities needed to locate files directly. The System utility focuses on system performance and configuration, Display deals with screen settings, and Indexing Options relates to the way files are indexed for search functionality, none of which manage file visibility in the manner required to locate a missing .dll.