IF you're referring to segregation, all the way from before its founding to 1964. Now, if you're talking about discrimination, they still are.
Answer:
D) The work of missionaries, like Saint Paul.
Explanation:
Christians were persecuted and murdered because of their faith before the coronation of Constantine as Roman Emperor. He made toleration of Christianity an official policy of the empire and after his death, the Christian faith became the official imperial religion. Before Constantine, the truths of Christ were spread by Jesus´Apostles first, then by missionaries, who managed to multiply the number of followers of the new religion.
The answer is D.
Gautama Buddha was confined to his palace by his father because an ascetic had propecised that he would become an ascetic if he sees the sufferings of life. The sights made him realise the impermanence of existence. It made him realise the sufferings of humans. These sights showed him that life is suffering and pain. after that event he decided to follow the path of the monk.
During the industrial revolution, more people were needed in factories than in farms. This migration from farms to cities was known as the business revolution.