在PL/SQL中定义一个可以存放雇员表（EMP）的员工名称（ENAME）的PL/SQL表类型，应该（）

• A、type array arr_type[emp.ename%type] index by binary_integer;
• B、type table arr_type[emp.ename%type] index by binary_integer;
• C、type arr_type is table of emp.ename%type index by binary_integer;
• D、type arr_type is pl_sql table of emp.ename%type index by binary_integer;