If B’s mother is A’s mother’s daughter, how is A related to B ?

Maternal Uncle Paternal Uncle Brother Father

Maternal Uncle

Note: ↑ or ↓ ⇒ Upward or downward line shown "generation gap" .    =    ⇒ Double lines shown "relation b/w Husband & Wife"    —   ⇒ single line shown "relation between them other than Husband & Wife".    +   ⇒ Plus sign shown " Male".    -   ⇒ minus sign shown " Female".