When Tracing the Execution of an Object by Hand, What

Multiple Choice

When tracing the execution of an object by hand, what is one way to indicate the change of an instance variable when a mutator method is executed?

A) Add a new index card for each change.
B) Cross out the old value and write down the new value.
C) Turn the card over and check the "mutator" box.
D) Put a check mark in the upper left corner of the index card.