A.200 B.232 C.208 D.210
A.0 B.1 C.2 D.1.5
A.有梯口梁,算至樓梯梁外側邊沿 B.有梯口梁,算至樓梯梁內側邊沿 C.無梯口梁,算至最上一層踏步外邊沿 D.無梯口梁,算至最上一層踏步內邊沿