A common feature of the earlier political parties in Nigeria was that they

The correct option for this question is "started as social-cultural organizations." The earlier political parties in Nigeria were not formed by the government, backed by colonialists or non-elitist in nature. Instead, they were mostly initiated by nationalists and activists who came together to advocate for the rights of their people. These parties started as social-cultural organizations aimed at promoting the cultural and social interests of their members, and later became political parties as the struggle for independence intensified. The most notable of these parties were the National Council of Nigeria and Cameroon (NCNC), the Action Group (AG), and the Northern People's Congress (NPC).