How many sisters does A have?
I) Parents of A have four children
II) A is the only son of his parents

A

if the statement I alone is sufficient to answer the question.

B

if the statement II alone is sufficient to answer the question.

C

if both the statements I and II are sufficient to answer the question but neither statement alone is sufficient.

D

if both the statements I and II together are not sufficient to answer the question and additional data is required.