Smells help to identify people, places, objects, other animals, etc. Taste is just as important as smell. For puppies, knowing the taste of its mother's milk is key for survival. A dog will rarely eat anything that doesn't entice his sense of smell. However, there is a dog or two or three out there that will eat just about anything.
Touch refers to the puppy s willingness to be touched by people.
Some puppies withdrawal and have the same reaction as they grow older while other puppies and dogs react positively when touched. Most dogs have exceptionally keen hearing. From birth, puppies have the ability to hear sounds we humans cannot hear. They can also detect sounds that are higher pitched. Puppies are extremely sensitive to the human voice and react according to the tone of your voice.