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Phil A.

Moderator emeritus
Apr 2, 2006
5,799
3,094
Shropshire, UK
I don't think there's an option to select a picture to insert into a reply, but you can paste a picture into a reply from the clipboard:
If you go into the Photos app first and long press on a picture you will get the option to copy that picture to the clipboard. Then, in mail when you are composing your reply, long press where you want to insert the picture and select paste.
 
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