— May I speak to Tom?    

— Sorry, he _____ Italy. But he _____ in two weeks. [ ]

A. has been to, will come back

B. has gone to, will be back

C. has been to, would come back

D. has gone to, won't come back

钢筋混凝土高层建筑结构的最大适用高度和高宽比分为A级和B级，关于两个级别的主要区别，下列中哪条叙述是正确的（）？

A.B级高度建筑结构的最大适用高度和高宽比较A级适当放宽

B.B级高度建筑结构的最大适用高度和高宽比较A级加严

C.B级高度建筑结构较A级的抗震等级、有关的计算和构造措施适当放宽

D.区别不大