Of the 4 the 2nd and 3rd are the best with the 3rd being the best of the 4. On the 1st and 4th you cropped to tightly. Puppies are like kids, you need to give them some room around them in the image. The 2nd one would have been very good except for the crop you chose. The vertical crop with the body going mostly horizontal throws it off for me...although had you gotten the whole body in it wouldn't have been better.
Good color, sharpeness and focus. Although the 1st and last one seem a bit over sharpened.
Cute puppy. Take lots of pictures now, they don't stay this young for long.