Nick Tech-Know Logo v2: Choices

I'm a freelance computer tech so this is for my computer and networking services business. The symbols and tools represent software, hardware, and networking. The devices represent the range of devices I service.
I need some graphic design critiques on this. This isn't my new logo design, so I hope I've learned some from my last one.

Update: added choice C... and now C2! Also did some typographic work on A and B. Hopefully the network cable bit in A is a bit more obvious now.