I think your 1st and 3rd explanations are a different way of saying pretty much the same thing. I think the 2nd one somewhat on the obscure side and I certainly wouldn't encourage child to look too deeply for possible alternatives or to express them in too complicated terms.
I always get pupils to take one aspect at a time and do a sweep through, eliminating the wrong rather than selecting the right. By aspects I mean colour, size, position, number etc.
So, with the one you have quoted, I would go right to left (the space being near the left hand side). I'd go large, small, large, therefore small, thereby stroking out a and b. Then I'd quickly say turn right, flip, turn right, flip, leaving you with just b. I would keep the language terms simple, too.
I certainly wouldn't have them look at the whole picture but focus on elements. If you get lucky, you may just pick the thing that eliminates all others.
E.g. On 11 on the same page, I would again look from right to left. Ignoring everything else that is going on, my eye is drawn to the top egg-timer which never moves position. This fact immediately eliminates a, b and d. This leaves you with just two possibilities. With only two left I often dwell on their differences to make my final selection--in this case c because of the middle row of balls.
On 10, I would approach colour first. I'd say to him black black black, black white black, black black black, black white black, therefore black black black. Stroke out a, b, d. Then you might do number i.e. no nicks (or whatever you want to call it) 1 nick, 2 nicks, 3 nicks, therefore 4 nicks so must be E.
While elimination may sound a bit laborious, they quickly get into the habit of doing it this way and it is ultimately quicker than simply studying the whole picture. Also, the less logical the child, the more they need a technique to rigidly follow.
From memory there is an acronym for the various characteristics. I think it is SPANSS --size, position, angle, number, shade, shape. But I am not sure how useful it is as far as the kids are concerned. I can see some of them wasting precious time, laboriously working their way through every one of these, when there is usually only 3 in play at any one time.
I hope some of these late night ramblings help.