If A $ B means B is father of A; A # B means B is mother of A; A * B means B is sister of A; A @ B means B is husband of A.
Which indicates N is grandmother of P?
I. P * Q # M $ N
II. P @ Q $ M # N
III. P # Q $ N * M
IV. None

Question: 以下哪项是正确的？
Options:
A. 以上各项均不成立, B. 仅 III, C. 仅 IV, D. 仅 I
Answer: C
True statement: IV