在我国北方烟区，斜纹夜蛾是一种常发灾害性害虫。

A、it is difficult to interpret
B、its meaning changes over time
C、it can communicate in different ways
D、critics and common people have different ideas

A、F-A=C＋B
B、F= C＋A＋B
C、F-A-C-B=0
D、F-C=A＋B