Concept:Military coups often follow serious failures in democratic governance, such as corruption and political disorder.
Explanation:Nigeria’s First Republic faced serious political crises after independence.
There were allegations of widespread corruption among public officials.
Elections were marred by malpractices, and violence broke out in several regions.
Political instability weakened the government and created public distrust.
These conditions made it easier for the military to justify taking over power.
External military threats were not the main cause.
The leaders did not refuse Western education, and independence was already achieved.
Therefore, the key factor was widespread corruption and political instability.
Answer:A. Widespread corruption and political instability