这是考察定语从句的用法,应填that was invited,当然,关系代词that 还可以换成who,但不能用whom,因为从句意:被他邀请的那个明星是我兄弟,可知先行词the star 在从句中作主语,故只能用that 或 who 引导。
that was invited
whom was invited
that was invited 还可以是who ...这里两个只能选that 作主语 whom只能作宾语