2. Which of the following method headers is most likely a header for a mutator method? a) public int getAgeO b) public double computeSalaryO c) public Person d) public void setAge(int newAge) e) none of these are headers for a mutator method 3. The reference always refers to the currently executing object. a) null b) static c) final d) actual e) this method. 4. A method that has multiple definitions is an a) overloaded b) overridden c) overlooked d) overclocked e) none of the above When two references point to the same object, a) a run-time error will occur. b) a compiler error will occur. c) the references are called aliases of each other. d) the object will be marked for garbage collection. e) the references are called null references