The following questions are based on a set of propositions I-IV
I All Ploys are Quoys
II Some Ploys are not Quoys
III Some, but not all, Ploys are Quoys
IV No Ploys are Quoys
Considered only by themselves, which of the following statements could both be true and false.
A) I II
B) II III
C) I III
D) I IV