If a monkey could choose its own juice, what kind of juice would it choose? The only way to find out - the only way - is to train a monkey to buy juice for itself. There are a lot of steps. First, you have to train the monkey to take money from you. Then you have to train the monkey to insert the money into the correct slot of a vending machine. Next, you must train the monkey to press the buttons on the machine to select the juice it wants. Once it brings you the juice, open the container so the monkey can drink from it to ensure that it actually wants that juice. Man, it takes so much work. We'll just save you the trouble: It's grape juice.