How to get a Business Visa and What type do i get is it F type or M type?

Hi there! I have an invitation letter from a company in PRC and its 6months Multiple Entry Business type.Been applied last jan 20,2016 but the embassy denied my papers.They didnt told me why my papers denied.Got invation letter,passport,passport photo copy,application form,bank certificate but my passbook before is not 6monts yet.and they ask me to have 100k in my accounts.What else do i need to get?? Please help me cause im trying to apply again soon..Thanks in advance and more power.