At least 300 million people are using QQ _       by Ma Huateng to chat on line.              [ ]

A. create                    

B. creates              

C. creating                  

D. created

氟康唑主要用于治疗皮肤和黏膜念珠菌病和马拉色菌感染，亦可用于治疗甲真菌病。