What do you mean which is better? Do you mean the style of martial art, which we prefer? When you ask a question, you have to be more specific and detail your questions. If you are doing this as a joke, then it is not funny and you just wasted people time....
Yes? What's the question? History, differences, likes/dislikes,.... throwing out a few words with a question mark behind them does not make it a question.
Edit: Better for what? They are not even in the same league. Do you like empty hand fighting or fighting with a sword?
Shorin Ryu Karate is an Okinawan empty hand fighting style. It's good for self defense if you have a teacher teaching it for self defense and not for sports and competition.
Kendo is Japanese, uses sword techniques for sparring with a shinai and is for competition.
Iado is Japanese swordsmanship and is the art of drawing the sword. Drawing the sword and cutting all in one move. A lot of the techniques are from a seated position.
Kenjutsu also Japanese swordsmanship has more stand up techniques and more beyond just drawing the sword.
Kenjutsu and Iado are very disciplined and use bokken and the sword for training. While the footwork of Kendo, Iado and Ken can help you getting out of the way of an attack it does not teach many strikes without a sword for countering. Iado and Ken are much more to learn discipline and to learn about a culture than they are for learning actual self defense. So if you are into Japanese samurai culture those would be the ones to go with.
If you are more specific with what you are looking for we can be more specific with answers.