A、Their dog knocked down something. B、A thief opened the window. C、The rain scraped against the window. D、A branch of rose bush

It was about half past eleven on a windy September night and Mr. and Mrs. Wilkinson had gone to bed early. They had put out the light and were just going to sleep when Mrs. Wilkinson heard a strange noise coming from downstairs. Mr. Wilkinson got up to investigate. When he reached the bottom of the stairs he noticed that the noise was coming from the dining room, and it sounded as ff someone was trying to open the French window that led into the garden.
    Mr. Wilkinson was quite frightened but he gathered up his courage, picked up a heavy walking stick and tiptoed into the dining room moving around the side of the room so that he wouldn’t be seen from the window. When he got to the window, he crouched down and peered cautiously round the edge of the curtain. To his relief, he saw that the noise was nothing more than a branch of a rose scraping against the window in the wind.