Using the View Filter you can make project trace images selectable or non-selectable.
To make project trace images 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 Project Trace Images row, click the filter icon in the Selection column to toggle selectability on or off.
Project trace image is selectable
Project trace image is not
selectable
Click OK.