how to build project to generate one dll

First of all Thanks for viewing my thread.

The scenario is that 

I  generate one dll call "A"

now i create a project call 'B'   and the project reference the "A " dll

when i build , the project generate A & B dll . 

what i want  just generate only one "B" dll , which it could containt "A" dll

is there any way to resolve it.

thanks for replying again.

Hope is a good thing.Maybe the best of things