Concept:Determine the family relationship using given sibling and parent-child links.Explanation:A and B are sisters.R and S are brothers.A's daughter is R's sister → this means A's daughter and R are siblings.Since A is the mother of her daughter, A must also be the mother of R (and thus of S, as S is R's brother).So A is the mother of R and S.Since B is A's sister, B is the maternal aunt of R and S.Thus, B is the aunt of S.Answer:Aunt