In seattle's speech, he states, "yonder sky has wept tears of compassion on our fathers for centuries untold".this statement is an example of
a. a simile
b. an allusion
c. technical nonfiction
d. personification

This statement is an example of PERSONIFICATION. The correct option is D.
Personification is a figure of speech which attributes human nature or characteristics to non human or inanimate objects. For instance, in the sentence given above, we are told that, the sky has wept tears of compassion' But of course, we all know that it is not possible for sky to cry; crying is an attribute of human beings. Also, the sky can not generate the emotions of compassion; that is for humans.Thus, the given sentence is an example of personification. 

Ok uhh exactly why is the question here