听力原文： Billy grabbed his fishing rod from the closet and headed for the back door. As he went out the door, he called to his grandmother that he would be back soon. When he reached the river, he put bait on his hook and threw the line into the water. Billy didn't have any friends so he always went fishing with his Grandfather. They always did the housework together first and then went fishing.
Sometimes Grandmother would pack their lunches and they would stay all afternoon. After his Grandfather died, he felt lonely and very sad. He had a hard time believing that his best friend wouldn't be with him anymore.
After Billy's Grandfather died he had to do extra housework. He tried to spend time with his Grandmother so that she wouldn't feel so alone. He could tell that she missed him be cause she cried a lot and it hurt Billy to see her cry. He kept himself busy so that he wouldn't feel so sad, but a hard as he tired, he couldn't help missing his Grandfather. Billy suddenly saw that his rod was moving, he must have caught a fish! The fish on the end of the line swam wildly in the water, but Billy fought with it until finally he had the fish on the bank. It was a large trout and Grandmother would be glad to have it for dinner. He showed her the fish and she smiled as she took it into the house to clean it. That night after he had gone to bed, Billy looked through his window at the stars and felt that his Grandfather was watching over him. One bright star stood alone and seemed to twinkle brightly. Billy looked at it for a moment before he said, "Goodnight Grandfather," and went to sleep.
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A. his parents.
B. his friends.
C. his grandparents.
D. his aunt and uncle.