Among the most popular: paternity and kinship testing , [u]which adopted children can use to find their biological relatives[/u] and [u]families can use[/u] to track down kids [u]put up for adoption[/u].关于本句语法的分析，下列选项正确的是（    ）。 A: to find their biological relatives 作目的状语 B: which adopted children can use… 为限制性定语从句，先行词为 kinship C: families can use… 与 biological relatives 并列 D: put up for adoption 是 kids 的同位语