The ____ HTTP status code indicates that the resource moved to another URL and should be automatically retrieved by the client software.

Which of the following statements are true?

a. Multiple constructors can be defined in a class. b. Constructors do not have a return type, not even void. c. Constructors must have the same name as the class itself. d. Constructors are invoked using the new operator when an object is created.

Analyze the following code:

``` public class Test { public static void main(String[] args) { Object a1 = new A(); Object a2 = new Object(); System.out.println(a1); System.out.println(a2); } } class A { int x; @Override public String toString() { return "A's x is " + x; } }``` a. The program cannot be compiled, because System.out.println(a1) is wrong and it should be replaced by System.out.println(a1.toString()); b. When executing System.out.println(a1), the toString() method in the Object class is invoked. c. When executing System.out.println(a2), the toString() method in the Object class is invoked. d. When executing System.out.println(a1), the toString() method in the A class is invoked.