What is the history between the nuer and dinka

They have been in conflict, but share common culture.

Explanation:

The Nuer and Dinka are the two largest South Sudan's tribes. The conflict between them has existed since the 19th century, due to certain geographic factors: they fought over grazing land and water for their cattle. During the dry season, Dinka and Nuer people migrated in search for water, often setting foot on land claimed by other tribes. This led to a mass conflict between them.

Some historians believe that the Nuer living on the east of Nile originate from Dinka. Although in conflict, these two tribes share common culture and language.The Nuer, Dinka and Atwot are often referred to as one ethnic group.

it would most likely be b. your welcome.