Click-to-Run is not a version of Office. Click-to-Run is a deployment technology for Office. A different deployment technology for Office is Windows Installer (MSI).
“All versions of Office, Visio, and Project that come with an Office 365 plan are installed by using Click-to-Run.
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Retail versions of Office, Visio, or Project for 2013 and 2016 are installed by using Click-to-Run.
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Some organizations purchase their software through volume licensing. Volume licensed editions of Office, Visio, and Project are installed by using Windows Installer (MSI).”
How to revert to an earlier version of Office Click-to-Run deployments.