Pointing to a man, a woman says, 'His mother is the only daughter of my father's only son.'
How is the woman related to the man?
I. Sister
II. Aunt
III. Mother
IV. Daughter

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