Vat or cst

There r 4 parties A B C & D. Suppose B purchased Raw materials for Pen(Refill, body, ink, int tube etc)from A & given all that materials to C for Manufacturing of FG i.e, PEN & paid the respective charges to C. Now if B wants to sell that pen to D, so plz suggest whether C will charge VAT in sale bill or will charge Excise duty. Plz Reply ASAP. And if B manufactures the pen by its own & not from C then what tax will be applicable at the time of sell of pen by B to D.