Tom______the USA. He____ back in two months.    [ ]

A. has gone to; comes    

B. has gone to; will be    

C. has been.to; comes

D. has been to; will be

全球通客户自带IPHONE5S/5C参加购机优惠，有哪些优惠内容和注意事项需要向客户说明？（）

A.优惠办理成功可赠送相应流量

B.必须办理4G主套餐

C.必须办理4G上网流量套餐

D.老客户升级4G套餐，次月生效