Ogaden region has been a source of conflict between which countries?

The Ogaden is a predominantly ethnic-Somali region in eastern Ethiopia that has been the focal point of interstate and local conflict between Ethiopia and Somalia. The most prominent episode was the Ogaden War (July 1977–March 1978), when Somalia invaded Ethiopia seeking to annex the Ogaden as part of a Greater Somalia project; Ethiopian forces, aided by Soviet and Cuban support, ultimately repelled the invasion, producing large refugee flows and sustained bilateral tensions [1]. Contemporary analyses and historical records therefore identify the Ogaden dispute specifically as a conflict between Ethiopia and Somalia, not the other country pairs listed, making option 4 the correct answer [1].

Sources

1. [1] https://history.state.gov/milestones/1977-1980/horn-of-africa