Preparing the family tree using the following symbols,
Using the notations, the diagrammatic representation of the question is as follows
1. Q is the only daughter of R, R is the wife of S.
2. P is the only son of S and P is married to M
3. T is the son of M and U is the sister of T, So the final family diagram is:
So, Q is the Paternal Aunt of U.
Hence, ‘Paternal Aunt’ is the correct answer.