How can I select shapes without their connector lines?

There are not that many ways to select in PowerPoint:

• It seems like the method of doing Ctrl+click on each shape is too tiresome
• The rectangles might be arranged in such a way that dragging a selection rectangle around them will fully include the rectangles but exclude the lines (by only partially including them)
• Using the Selection Pane via Home > Drawing group > Arrange and selecting "Selection Pane" will show all the elements on the right, with the rectangles usually named "Rectangle #", so they are easier to pick out. However, multi-select is still by Ctrl+click.
• Write a VBA macro to select all rectangles is more complicated.