A29915. 下面的描述中，（ ）不能正确定义一个名为 Student 的结构体以及一个包含20个元素的结构数组。

struct Student {

      string name;

      int age;

      float score;

};

struct Student students[20];

struct Student {

      string name;

      int age;

      float score;

};

Student students[20];

struct Student {

      string name;

      int age;

      float score;

};

Student* students = new Student[20];

struct Student {

      string name;

      int age;

      float score;

};

Student students = new Student[20];