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];