I will start by saying that what I look for is not necessarily what everyone else will look for in images. #1 just doesn't do anything for me at all. I am not a fan of the line in the background and the two unfrosted cupcakes in the back. My eye starts with the in focus ones in the front and quickly goes to the back, leading me to wonder where the frosting is, and not coming back to the image. #2 I like this the best of the three. The limited depth of field does a good job of drawing attention to the cupcake that you want. What I don't like about it is the open space on the right. Cupcakes going off the left side of the image and blank space on the right. I do like the unwrapped cupcake and it makes it look inviting to me. #3 Similar to #2 with the open space, but I don't like the looks of the square cupcake. Has it been eaten and returned to the wrapper, etc.?
So to me, move the center image to the right and you have a pretty decent image.