It was already dark when an old man arrived at a small town. He found an inn and wanted to stay there for the night. After he had entered his room, the owner said to his wife, “Look at his luggage, dear. It’s heavy and the old man is so careful about it that he takes it wherever he goes. I’m sure there are lots of valuable things in it. I want to steal some when he is asleep.”
“No, no,” said the woman. “He must search for what was gone tomorrow morning. Then he’ll take you before the judge.” They thought and at last the woman had an idea. “We have forgetful grass,” said the woman, “Why not put some into his food? If he has the food, he will forget to take his luggage away.” “How clever you are! My dear.” said the owner, “Don’t forget it when you prepare supper for him.”
The old man had the food with the forgetful grass and went to bed. The next morning, when the owner got up and hurried to the room that the old man lived in, he found the door was open and the old man had left with his bags. He woke his wife up and said angrily, “What a fool! Your forgetful grass isn’t useful at all.” “No, no,” said the woman. “I don’t think so. The forgetful grass does always work. He must have forgot something.” “Oh, I’ve remembered!” The owner cried out suddenly, “He forgot…”
The owner and his wife put the forgetful grass into the food because _______.

A．the old man always forgot something

B．they wanted to make the food better

C．they hoped the old man would leave the bags in the inn

D．they wanted to know if the grass was useful

According to the passage the old man forgot _______.

A．to take his bags away

B．to tell the owner when he left

C．to close the door when he went to sleep

D．to pay them the inn money

Which of the following statements is TRUE according to the passage?

A．Both the owner and his wife were clever.

B．The owner of the inn got nothing from the old man.

C．The old man left the inn without his bags.

D．The woman forgot to put the grass into the food.