Final answer:
Klingon is not a language spoken in contemporary African theatre; it's a fictional language from Star Trek. Swahili, Yoruba, and Hausa are the actual African languages used. Great Zimbabwe is the empire not located in West Africa.
Step-by-step explanation:
The language that is not spoken in contemporary African theatre is c) Klingon. Swahili, Yoruba, and Hausa are languages indigenous to Africa and are used in various forms of cultural expression, including theatre. Klingon, however, is a fictional language created for the Star Trek media franchise and does not have roots or usage in African culture or theatre.
Similarly, addressing the other questions listed, the empire that was not in West Africa is a) Great Zimbabwe, which was located in Southern Africa. Additionally, a) the European Union (EU), b) the North Atlantic Treaty Organization (NATO), and d) the African Union (AU) are all regional intergovernmental organizations (IGOs), but the c) International Court of Justice (ICJ) is not a regional IGO but a global judicial institution.