For the Questions Below, Consider the Following Class Definition

For the questions below, consider the following class definition:
public class AClass
{
protected int x;
protected int y;
public AClass(int a, int b)
{
x = a;
y = b;
}
public int addEm( )
{
return x + y;
}
public void changeEm( )
{
x++;
y--;
}
public String toString( )
{
return "" + x + " " + y;
}
}
-Which of the following is True regarding Java classes?

A) All classes must have 1 parent but may have any number of children (derived or extended) classes
B) All classes must have 1 child (derived or extended) class but may have any number of parent classes
C) All classes must have 1 parent class and may have a single child (derived or extended) class
D) All classes can have any number (0 or more) of parent classes and any number of children (derived or extended) classes
E) All classes can have either 0 or 1 parent class and any number of children (derived or extended) classes