According to the companies' websites, the number of active QQ users in China has reached 1 billion, while Qihoo 360 also claims _______ at least 300 million users before June 2010.[ ]

A. to have  

B. to have had      

C. having    

D. having had

应收账款包括下列各种应收款项（）。

A.销售商品应收的货款

B.职工预借的差旅费

C.提供劳务应收的账款

D.应收铁路部门的赔款