It has been proved _____ eating vegetables in childhood helps to protect you against serious illnesses in

latter life.     [ ]

A. if                                        

B. because

C. when                                        

D. that

某粉土地基进行了振冲法地基处理的施工图设计，采用振冲桩桩径1.2m，正三角形布置，桩中心距1.80m。经检测，处理后桩问土承载力特征值为100kPa，单桩载荷试验结果桩体承载力特征值为450kPa，现场进行了三次复合地基载荷试验（编号为Z1、Z2和Z3），承压板直径为1.89m，试验结果见题19表。问振冲桩复合地基承载力取值最接近（）。

A．204 kPa

B．260 kPa

C．290 kPa

D．320 kPa