Blood Relations

Concept:We need the relation between $T$ and $R$ using family links.Explanation:$X$ and $Y$ are brothers. $R$ is father of $Y$, so $R$ is also father of $X$ (full brothers).$S$ is maternal uncle of $X$ ⇒ $S$ is brother of $X$’s mother.Also $S$ is brother of $T$ ⇒ $T$ is sibling of $S$.Since $S$ is brother of $X$’s mother, $T$ must be that mother herself (sister of $S$).Thus $T$ is mother of $X$ (and also of $Y$, as they are full brothers).$R$ is father of $Y$, hence $T$ and $R$ are husband and wife.So $T$ is $R$’s wife.Answer:Wife