An author who wrote a work that served as the source of hamlet was select all that apply.

saxo grammaticus
thomas kyd
christopher marlowe
michel de montaigne

The answer is: Saxo Grammaticus and Thomas Kyd

From the option there are two related to Shakespeare work “Hamlet”, the first is Saxo Grammaticus,  one of the sources related to the story of Hamlet is a Scandinavian version called Amleth included in Gesta Danorum around 1200 AD by Danish historian Saxo Grammaticus, and the other is an earlier play possibility written by Thomas Kyd that now is called Ur-Hamlet.

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.