If you are not seeing the Select Button or the Trash Icon try
[list=1] [*]restart your iPad (Press and hold Sleep/Wake button until the shut down slider appears then move the slider from left to right. Once the shut down is complete (this can take some time) press and hold the Sleep/Wake button until the Apple logo appears.
After the Apple logo appeared, there was a brief period of black followed by the appearance of the password-entry window. I entered and the photo software was operating the same as before.
[*]if 1 does not solve the problem try a hard reset. Press and hold the Sleep/Wake button and the Home button until the slider appears then keep holding until the screen goes blank and the Apple logo appears.
This didn't work either. I was expecting the white line to appear under the logo but nada. Again, I entered and the photo software was operating the same as before.
FYI, "operating as before" means I have the select function but only one option, to send the photos via email et cetera. But, no Trash Can in sight. So, I guess I'll be moving to option 3.
I continue wondering if it's because I have not enabled iCloud and this is Apple's way to force my hand.
In another thread, joemikeb mentioned doing it easily through the cloud...not your preferred method of doing anything.
EDIT: About the option 3 - doesn't that mean I'd just be putting 10.2 back onto the iPad as opposed to going back to 9.3.5 ?