单项选择题

沿疏散走道设置的灯光疏散指示标志,间距不应大于(),对于袋形走道,不应大于(),走道转角处不应大于()

A.20m,15m,0.5m
B.15m,10m,1m
C.20m,10m,1m
D.20m,10m,0.5m