【单选题】

The author focuses primarily on
A．(A) presenting two competing scientific theories for the cause of post-industrial climate change and evaluating the body of evidence behind each one

B．(B) giving a brief overview of some recent scientific developments in solar physics and explaining their possible implications for future research
C．(C) discussing the successes in linking terrestrial phenomena with solar activity and indicating how they may have an impact on preventing further climate change
D．(D) pointing out the success of a certain line of scientific inquiry into the terrestrial effects of solar activity while qualifying its successes with regard to climate change