Turn off selection coloring

[Harry Putnam]

I'll admit I only spent about 10 minutes looking for this answer... I
did

M-x apropos <RET> selection <followed by just `select'>

M-x customize-apropos " ditto "

C-h -i m emacs i select (and walked thru them)

I didn't find out how to turn off the blue color that appears when
mark is set, and I scroll. Indicating a selected region.  The one that
requires two spc bar hits to turn off.

I liked the old way... with no color and find myself very often
accidentally coloring a region... 

It is nice when I *intend* to select a region but too often I
accidentally select.... no doubt some kind of poor typing habit
causing it but it means this happens very often for me.

I don't remember having trouble knowing what I selected... when
intentionally selecting a region before we had that highlight, so I
think I want it off.

Can anyone provide a better searching clue?