Zhang San went to a store to buy chocolates, and the owner showed him four boxes, and each box wrote a sentence. The first box: "Litchi in all boxes. " The second box: "Apples in this box. " "The third box:" There is no chocolate in this box. "The fourth box:" Some boxes have no litchi. "The owner said to Zhang San," There is only one truth in the four sentences, which box do you think the chocolate is in? " in?". Please choose the correct answer for Zhang San. ['Chocolate in the first box.', 'Chocolates in the second box.', 'Chocolate in the third box.', 'Chocolate in the fourth box.']