Answer the following questions on the basis of information given below.
A - B means A is the sister of B.
A + B means A is the mother of B.
A % B means A is the brother of B.
A # B means A is the son of B.
How is X related to U in the given expression?
Y # X + Z % U + M
1
Step-Sister
2
Mother
3
Aunt
4
Mother-in-Law