Did you think Programmer B showed initiative but that Child B cheated?

It depends:

1. Did Programmer B comply with the licensing terms of the source code he downloaded?
2. Was the source code of equal quality to the code written by Programmer A?
3. Was the code meant to just get a job done, or was its purpose to improve the programmer's skills as well?

One thing is fairly clear, The As will have learned more than the Bs. Come next assignment we'll see who does the better job. I believe The Path to Mastery touches on this as well.