阅读短文, 选出正确答案。

（A）

   A picture is on my desk. It is a picture of Mary's family. The man is her father Mr. White. He is a doctor. A woman is behind Mary. She is her mother. She's a teacher. A boy is in the picture, too. He is Mary's brother, Sam. Mary and Sam are in the same school. But they aren't in the same grade. They look like their mother. The White family are English. They come from London.

正确选择。

角：①牛、羊、鹿等头上长出的坚硬的东西。

  ②形状像角的。

  ③物体边沿相接的地方。

小明家的老黄牛，长着一对又粗又尖的角____。在拴牛的墙角____处，一棵高大的皂荚树，结满了皂角____果。

印度在20世纪60年代推行的“绿色革命”，其主要目的是为了解决（    ）