The third stanza is the answer
Slavery
"was laughed at and made out fun on account of his look and the sound of his voice.
B sounds like the logical answer (I might be wrong though )
Boxing career of Muhammad Ali. This is the latest accepted revision, reviewed on 29 April 2020. Cassius Marcellus Clay Jr. so therefore he chose boxing
"Then" is used in an "if-then" scenario, to dictate chronological order. In other words, "If you jump off, then you will fall," or "he was attacked and then retreated."
"Than" is used for comparisons. In other words, "The egg was bigger than the pea," or "I'm stronger than you."