AMC 12A 2003 Problem 6

Define x \heartsuit y to be |x-y| for all real numbers x and y. Which of the following statements is not true?

Answer Choices
A. x \heartsuit y=y \heartsuit x for all x and y
B. 2(x \heartsuit y)=(2 x) \heartsuit{P}(2 y) for all x and y
C. x \heartsuit 0=x for all x
D. x \heartsuit x=0 for all x
E. x \heartsuit y>0 if x \neq y