True
False
The CLR traps any use of a null reference and notifies the program of the error by throwing a NullReferenceException.

True
False
Passing an object of a class type by value copies only the reference, the object itself is not copied.

An array of instances of that class
An array of object references
An array of references of the class type
An array of a class type is an array of references of that type. Creating the array does not create any instances of the class.

True
False
Garbage collection is a relatively expensive operation and should only be performed periodically. Generally speaking, it is best to let the CLR invoke the garbage collector whenever it determines it is necessary.

The == operator
The Equals method
The Object.ReferenceEquals method
The Object.ReferenceEquals method performs an identity test; that is, it compares references to determine if they refer to the same or different objects.