The author advances the plot through the use of the narrator's .
a) discussion with peers in a medical library
b) page-by-page study of a medical text
c) detailed recollected of his doctor's advice
d) struggle with painful physical symptoms
(this is from the article: three men in a boat by Jerome K. Jerome)

struggle with painful physical symptoms

Explanation:

remember that he went to the british museum, and he was trying to read up the treatment for his fever, but then read more and self diagnosed himself with almost everything in the book, it was never his doctor who diagnosed him with all these diseases. (not fully sure, this is just a guess)

harlem's  cotton club boasted the talents of duke ellington. singers such as bessie smith and billie holiday popularized blues and jazz vocals. jelly roll morton and louis armstrong drew huge audiences as white americans as well as african americans caught jazz fever.

the symbol of the grandfather's heritage in this excerpt from "the medicine bag,” is the beaded bolo tie.

a bolo tie is a cord fastened around the neck with an ornamental clasp which is worn as a necktie. they have been used by native american tribes such as hopi, navajo, zuni, and puebloans since the mid-20th century.

therefore, the fact that the grandfather is wearing a bolo tie refers to his heritage as native american.