Answer:

Part A: Just one object. All four reference variables point to the same object. (Optimization creates just one object if the characters are the same.)

(In a sensible program, those four declarations might have been spread out over many lines.)

Part B: Four new objects, each containing the same characters. Think of them as Xerox copies. Four distinct objects that look the same.

(The next chapter discusses this further, in case you are a little unhappy about these answers.)

End of the Chapter

You may wish to review the following. Click on a subject that interests you to go to where it was discussed.

object, characteristics Three characteristics of objects.
objects, as memory What software objects are made out of.
members of a object Members of an object.
von Neumann von Neumann computers.
class, definition What a class is.
cookie cutters Cookie cutters and cookies
static The static modifier.
static method static methods
virtual machine, startup How the Java virtual machine starts a program up.
constructor Constructors
parameter Parameter
dot notation Dot notation.
constructor, in declaration Using a constructor in a variable declaration.

The next chapter discusses object references.