I would rather be mute. I am quiet as it is. I love music and I love to see the beauty of Mother Earth. Muteness wouldn't be too bad I suppose since I am quiet.
Forget those three; I'm going with something practical. I think I'll go for the inability to taste anything. I keep my sight, hearing, touch and voice, and gain the ability to eat vegetables for every meal.
I doubt that I could mentally handle the loss of any of my senses, even taste. Senses are the ways in which living things take in their surroundings, and process information. Being mute, if I had to choose between the options given, would be the desired affliction. Speaking is but one form of externalizing thoughts, and displaying emotions. There are others that I can use in lieu of that though; I can write, I already have a tendency to use body language (though crude at times). Not being able to speak would ultimately be a minor loss in my eyes.
Right now, I would have to go with blind. A part of me wants to be deaf, but then I wouldn't be able to speak my story. Being blind, I would still have many of my life experiences, I rarely go out anyway, and my imagination would go wild with what I think the world is like.
Blindness would be the worst! You lose access to all the wonders of the internet. Everyone on here would be unreachable. If you're mute, you can still type your story, or write it. Then it has more chance of lasting, as texts last longer than speeches by several thousand years.
I think I'll rather be mute, I have a pathetic excuse for a voice anyway so I hardly speak up. If I was too be blind or deaf I think I couldn't deal with it.