Historical materialism is a kind of determinism, which holds that the development of society is determined by objective material conditions, and people's subjective will will will not affect the development of the whole society, and society will develop according to its established historical laws. So you should choose a.

As for a, historical materialism does not pay attention to the ideological motivation of human activities, because it believes that human subjective motivation will not affect the development of history.

B. Historical materialism holds that economy and productivity, not politics, play a leading role in social life.

D, I don't see the relationship between this option and the problem.