We will have modern equipment ______ things that are complicated. This will make things simple.      

A．to assist us with

B．assist us to

C．to assist us in

D．assisting us with .

开业仪式，是指在______，______，______，或是______之际，为了表示庆贺或纪念，按照一定的程序隆重举行的专门的仪式。