Adding rows to SQL table depending on key values from another table

I have three tables.

Table A - Vendor Contracts Table
Table B - Vendor Agreement Details
Table C - Vendor Agreement codes and descriptions

What I need to do is for every vendor in table A,  add rows to table B for each of the rows in table C.

So for instance I have Vendor 1234567890 in Table A, I want to add rows to table B for that vendor for every "Vnn" row in table C.   "Vnn" is just a serious of codes from V1 - V9.  

There are currently a total of 9 "Vnn" codes and there respective descriptions in Table C.   So in Table B I would end up with the following:

Vendor                           Code
123456789                      V01
123456789                      V02
"
"
"
123456789                      V09

and of course for each of the other Vendors in table A.


No need to worry to much about what other columns will be selected/added.  I just need to know what the structure/syntax would look like to do this.