单项选择题

A、Δ=(69.8–70)/(100-10)*100%=-0.22%
B、Δ=(69.8–70)/100*100%=-0.2%
C、Δ=(70–69.8)/(100-10)*100%=0.22%
D、Δ=(70–69.8)/100*100%=0.2%