The term "abate" in Line 9, Para. 2 possibly means ______.

A．illustrate the influence they have on the issue of gun control
B．refute the claim that private ownership of firearms will deter violent crimes
C．support the thesis that gun ownership leads to more violence
D．show the necessity of method improvement in the study of gun ownership history

A．advocates private ownership of firearms
B．is not objective in his analysis
C．has analyzed a wrong period
D．has cited dubious statistics