问题：

[单选]

You work as an application developer at Certkiller .com. You have been given the responsibility of creating a class named CalcSalary that will determine the salaries of Certkiller .com’s staff.The CalcSalary class includes methods to increment and decrement staff salaries.You would like to invoke the IncrementSalary and 
DecrementSalary methods dynamically at runtime from the sales manager application when needed. After viewing the information displayed in the exhibit， you decide to use the Salary delegate to invoke these methods.  using System； 
public delegate boolSalary （Employee Emp， double Amount）； public class CalcSalary { 
// for promotions 
public static bool IncrementSalary （Employee Emp， double Amount） { 
// implementation details } 
// for demotions 
public static bool DecrementSalary （Employee Emp， double Amount） { 
// implementation details } 
What code should you use？（）

A . A
B . B
C . C
D . D