The Metaphosphate Ion, PO₃^-, Is the Structural Analog of the NO₃^-

The metaphosphate ion, PO₃^-, is the structural analog of the NO₃^- ion with respect to the arrangement of the atoms in the ion. After drawing the "best"Lewis structure for the metaphosphate ion based on formal charge considerations, what is the number of resonance structures for this "best"Lewis structure? Hint: Use formal charge to help determine how many realistic resonance structures there are for the metaphosphate ion.

A) 1 (no resonance structures)
B) 2
C) 3
D) 4
E) 5