单项选择题

The growth of switching has 21 a new generation of network management tools that help 22 cope with the challenges, 23 them to correlate device alarms in order to 24 pinpoint root causes, or to monitor service levels without depending on IP subnet schemes. These new tools have become essential to coping with the primary 25 effect of any treatment that significantly increases network flexibility: added complexity.

A.better
B.well
C.welly
D.good