It is often difficult for a man to be quite sure what tax he ought to pay to the governmen
There was a certain artist who was always very careful to pay the proper amount.
One year, after posting his check as usual, he began to wonder if he had paid enough, and after a lot of work, with a pencil and paper, he decided that he had not. He believed that he owed the government something.
He was just writing another check to send to the tax-collector when the postman dropped a letter into the box at the front door. Opening it, the artist was surprised to find inside it a check for five pounds from the tax-collector. The official explained that too much had been paid, and that therefore the difference was now returned to the taxpayer.
It is mentioned in the passage that one has to pay tax according to ______.
A.how much education one has received
B.whether one is single or married
C.how old one's children are
D.where one lives