[求助]OG84

84. One legacy of Madison Avenue's recent campaign to appeal to people fifty years old and over is the realization that as a person ages. their concerns change as well.

(A)     the realization that as a person ages, their

(B)         the realization that as people age, their

(C)     to realize that when a person ages, his or her

(D)     to realize that when people age, their fficeffice" />

(E)         realizing that as people age, their

In choice A, the plural pronoun their does not agree in number with the singular noun person. Choices C, D, and E can be faulted for failing to complete the construction One legacy ... is with a noun that matches the noun legacy; these choices use verb forms--the infinitive to realize or the present participle realizing--in place of a noun such as realization(be动词前后要求并列). Further, when in C and D is less precise than as in characterizing a prolonged and gradual process such as aging(体会其中意思的细微差异). B is the best answer.

我认为their可能是用来修饰前面的复数名词，前面的复数名词有people，years，ages，是不是their的指代对象不明？

还有，怎么才能正确的找到代词的指代对象呢？如这里的their，是不是在找their的指代对象时只要在that这个从句的范围里就可以了