单项选择题

A.小于6/18(0.3)到光感,或视野半径小于10°
B.小于6/12(0.5)到光感,或视野半径小于10°
C.小于6/18(0.3)到光感,或视野半径小于5°
D.小于6/18(0.5)到光感,或视野半径小于5°