The answer is: B. social reforms should not be implemented because they interfered with the natural progression of society
Social Darwinist generally believed that the society itself run based on the survival of the fittest principle. Meaning that those who achieve high social status in society are the people who managed to won the survival competition with other people.
They see social reforms as government's way to reward the people that lose the 'competition' and interfered with natural progression of society.