Concept:Two successful military coups in Nigeria removed civilian governments and replaced them with military rule.
Explanation:The first was on
15 January
1966, when soldiers led by Major Chukwuma Nzeogwu overthrew the civilian government of Prime Minister Abubakar Tafawa Balewa.
The second was on
31 December
1983, when Generals Muhammadu Buhari and Tunde Idiagbon removed the civilian government of President Shehu Shagari.
The other coups listed in the options, such as those of
1975,
1976, and
1985, removed military regimes, not civilian governments.
Answer:D. January 1966 and December 1983