For the subpublic class Employee of the base public class Person example provided in the tutorial, what if you need to keep track of the department for each employee.

What code segment could be used to properly initialize, and add methods to set and get this value?

a$.)$

public class Employee extends Person $\{$

private int employeeId;

private double salary;

private String department;

public Employee$($String firstName,String lastName,String jobTitle,double sal,int empId,String department$)\{$

super$($firstName$,$lastName,jobTitle$)$;

this.employeeId $=$ empId;

this.salary $=$ sal;

this.vacationDaysPerYear $=14$;

this.vacationDays $=$ this.vacationDaysPerYear;

this.department $=$ department;

$\}$

public void getDepartment$($department$)\{$

return "Department: $"+$ department;

$\}$

public String setDepartment$()\{$

this.department $=$ department;

$\}$

$\}$

b$.)$

public class Employee extends Person $\{$

private int employeeId;

private double salary;

private String department;

public Employee$($String firstName,String lastName,String jobTitle,double sal,int empId,String department$)\{$

super$($firstName$,$lastName,jobTitle, department$)$;

this.employeeId $=$ empId;

this.salary $=$ sal;

this.vacationDaysPerYear $=14$;

this.vacationDays $=$ this.vacationDaysPerYear;

$\}$

public String getDepartment$()\{$

return "Department: $"+$ department;

$\}$

public void setDepartment$($String department$)\{$

this.department $=$ department;

$\}$

$\}$

c$.)$

public class Employee extends Person $\{$

private int employeeId;

private double salary;

private String department;

public Employee$($String firstName,String lastName,String jobTitle,double sal,int empId,String department$)\{$

super$($firstName$,$lastName,jobTitle$)$;

this.employeeId $=$ empId;

this.salary $=$ sal;

this.vacationDaysPerYear $=14$;

this.vacationDays $=$ this.vacationDaysPerYear;

this.department $=$ department;

$\}$

public String getDepartment$()\{$

return "Department: $"+$ department;

$\}$

public void setDepartment$($String department$)\{$

this.department $=$ department;

$\}$

$\}$

d$.)$

public class Employee extends Person $\{$

private int employeeId;

private double salary;

private String department;

public Employee$($String firstName,String lastName,String jobTitle,double sal,int empId,String department$)\{$

super$($firstName$,$lastName,jobTitle$)$;

this.employeeId $=$ empId;

this.salary $=$ sal;

this.vacationDaysPerYear $=14$;

this.vacationDays $=$ this.vacationDaysPerYear;

emp$\_$department $=$ department;

$\}$

public String getDepartment$()\{$

return "Department: $"+$ department;

$\}$

public void setDepartment$($String department$)\{$

emp$\_$department $=$ department;

$\}$

$\}$