Using the View Filter you can make text selectable or non-selectable.
To make text selectable or non-selectable:
Select View
> View Filter or click the View Filter button on the Basic View
Control or Advanced View Control toolbar.
In the View Filter dialog, select the Notation tab.
In the Text row, click the filter icon in the Selection column to toggle selectability on or off.
Text is selectable
Text is not selectable
Click OK.