A

    TheSoundofMusic is one of the most popular American movies. And the song DoReMi in the movie is also popular in the world.

The movie tells a story about a tutor, Maria. She is a young and outgoing woman. She goes to look after a family with seven children. Their family name is Von Trapp. Mr. Von Trapp is a captain. He and his family live in Austria.

    The family are very sad after the children's mother, Mrs. Von Trapp, died. Nobody takes care of the children. They cry and shout every day. The lonely father often becomes angry because of the noisy children.

    Maria often teaches them to sing lively songs and perform short, funny plays. At first the father is almost mad, but the children's smiling faces make him happy again. Then Mr. Von Trapp falls in love with Maria. At last they get married.

如图所示，早晨的太阳光斜射到一块水平放置的平面镜上，经镜面反射后，反射角为　 ____　，随着时间的推移，从早晨到中午，反射角将 ____（选填“增大”、“不变”或“减小”）．

生老病死是一种自然现象，但受社会经济条件制约。读图，完成下题。