We are asked for the primary purpose of the second paragraph.
Prephrase: Alright the second paragraph talked about shared aspects of blues and spirituals and attributed these shared aspects to African American and West African culture.
Here is a breakdown of the 2nd paragraph:
Lines 21 - 25: Starts out talking about an aspect of African American folk tradition
Lines 25 - 31: Talks about how blues & spirituals both have the aspect mentioned in the previous sentence in common
Lines 31 - 36: Talks about how this shared aspect might be linked to West African and African American ancestral cultures
Lines 36 - 41: Clarified the meaning of the word "ecstasy" which refers to the psychological condition invoked during religious experiences.
(A) This is exactly what we want. Everything in the paragraph seems to point towards talking about the shared aspects of blues & spirituals as a way uncovering the shared origins of the two mediums in both African American folk traditions and West African and African American cultures.
(B) We are told what ecstasy means as it is used in the 2nd paragraph, but there is no examination of how it is produced. This would be far too narrow of a way to describe the primary purpose of the second paragraph.
(C) "Identify the musical precursors . . ." There is no mention of specific musical precursors of the blues in this passage. There is mention of shared origins, but not specific musical art forms that came before the blues.
(D) There is mention of how African American folk tradition does not separate the spiritual and sacred. There is also mention of the spiritual aspects that blues has in common with spirituals, but the primary purpose of this paragraph is not explore sacred and secular strains of blues, but to talk about similarities between spirituals and blues and use that as a vehicle to uncover what may be their shared origins.
(E) This answer choice is too broad. We do uncover the early origins of two kings of African American folk arts - blues & spirituals, but we do not trace the early development of the African American folk tradition.