【名词&注释】
建筑物安全(building safety)、建筑地基基础设计规范、土质条件(soil condition)、由上而下(from top to bottom)
[单选题]单桩桩顶作用轴向力时,桩身上轴力分布规律为()
A. 由上而下(from top to bottom)直线增大
B. 由上而下(from top to bottom)曲线增大
C. 由上而下(from top to bottom)直线减小
D. 由上而下(from top to bottom)曲线减小