Concept:A vending machine can only sell items that are small, pre-packaged, and easily dispensed without human assistance.
Explanation:Vending machines are designed to hold and release products that have a fixed size and shape.
Snacks, tea, and tickets are all suitable for vending because they are sold in standardised packaging or can be printed and delivered automatically.
Shoes, however, come in many different sizes and styles, and customers usually need to try them on before buying.
It is not practical for a vending machine to stock, display, or choose the correct shoe size for a customer.
Therefore, shoes cannot be sold through a vending machine in the normal retail sense.
Answer:The option that CANNOT be sold through a vending machine is A. shoes.