A、They save time and money. B、They sell better quality merchandise. C、They are time-saving and convenient. D、They are impersonal

Vending machines sell many different types of items. Some of them sell cold drinks like soda, or hot drinks like coffee or hot chocolate. Others sell candy, stamps, tickets, newspapers, and other types of small merchandise.
    These machines have been successful for two reasons. They save time and they are convenient. Merchandise sold in machines eliminates the need for a salesclerk or cashier. In many places the customer can use the machines at any time of day or night.
Although there are many different sizes and types of vending machines, they all work in basically the same way. The customer puts a coin into the machine and then pushes a button, pulls a lever, or opens a door to receive the merchandise.
    Q22: What do you know about vending machines?
    Q23: Which of the following is NOT sold by vending machines according to the passage?
    Q24: Why are vending machines so successful?