In What Way Does Tsuda See Cultural Differences as Productive

In what way does Tsuda see cultural differences as productive in ethnographic research?

A) Conflicts within the community provide "events" for analysis.
B) As outsiders, anthropologists can serve as key advocates for their informants.
C) Cultural differences between researchers and researched highlight the emic/etic binary.
D) Tsuda gained more new knowledge from Japanese Americans who were from other generations.