This is from the great correct answer only !

what does the valley of ashes symbolize?

a. the american dream

b. death and dying

c. the moral and social decay that results from the uninhibited pursuit of wealth

d. the essential meaninglessness of the world

8. b

9. d

10. e

11. a

12. c

i think thats it

in the following paragraph, the fourth sentence the correct answer is: three personal subject pronouns

”she was embarrassed when she found that they had been put back on the shelves…”

a   subject pronoun is a personal pronoun. i, you, he, she it, we, they.  

in the sentence it can be observed she, used twice and they used once. is for this reason that is a three personal subject pronoun sentence.