Read the following statements and answer the question on their basis.
A @ B means that A is the mother of B.
A # B means that A is the father of B.
A $ B means that A is B 's brother.
A % B means that A is sister of B.
In expression A $ B # C @ D, how is B related to D?
1
Brother
2
Maternal uncle
3
Maternal Grandfather
4
Father