What originally prompted malcom x to educate himself

What prompted him was that he was imprisoned.

Malcolm X taught himself from dictionaries and books how to become literate. This literacy prompted Malcolm X to find an interest in history, but not just history, the history "white men" left out. He became further interested in this topic, and found himself dig deeper and deeper and he gave all the credit to the homemade education he gave himself in prison.

The third answer is correct.