According to the passage which of the following statements is a major factor that blocks

According to the passage, which of the following statements is a major factor that blocks the preventive action？

A．The developing world is unwilling to take preventive action.

B．People think the developed world should take more responsibility.

C．People do not consider the preventive action an urgent task.

D．Harmful emissions are hard to reduce in the developing countries.

请帮忙给出正确答案和分析，谢谢！