There is a sentence in the second paragraph: "In a hundred closed cafes the espresso machines give an expiring hiss, as if at last slipping off their shoes and wiggling their toes. " How do you understand this sentence？

A. It means that the coffee machines have been used for too much and cannot be used any longer.
B. It implies that the owners of these cafes are so tired that they just want to have a good rest.
C. It suggests that the owners of these cafes have lost their shoes and their toes feel painful with cold．
D. The coffee machines are going to stop working; it is just like what a person does before he goes to bed after a day's hard work.