I seem to go round and round in the Adobe help pages. A note would say this is only for standalone versions and when you get to the page, it say cc
There is no trial version for Lightroom 6. If you want to use the trial option then you need to install Lightroom CC. At the end of your trial you can convert it to a standalone product with a purchased serial number. Here are the instructions:
Adobe Photoshop Lightroom Help | Serialize Lightroom CC trial to activate as Lightroom 6
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