阅读理解，根据短文的意思，选择最合适的答案。
    This is a picture of a family. The grandmother's name is Harry Smith. The grandfather's name is Jean Smith. They are very old. They are Americans.
    The father's name is Lake Smith. He is 44. The mother's name is Kate Smith. She is 40. They have a son of ten and a daughter of fifteen. The son's name is John Smith and the daughter's name is Mary Smith. They are students of No.12 Middle School. Kate is a teacher of the same school. Lake is a policeman. It is a very good family.