D
where=in which
那么这句话就可以变为：We are going to spend the Spring Festival in Guangzhou ,in which live my grandparents and some relatives. 因为live后面要加in,所以用in which是合理的,which指代Guangzhou,那么就是My grandparents and some relatives live in Guangzhou,对吧?
以后你做题就这样代入,看where是不是可以换成in which,如果可以,能么这句定语从句就成立
希望我的回答能帮助到你O(∩_∩)O哈!有不懂的继续问我噢~