I mean. . . the most of all of those you feel like spending?
I’d say video card first. Probably NVIDIA as Blender’s support for NVIDIA’s features seem to be ahead of AMD’s. (Do your research and look at bench marks and price/performance/watt)
Ram, definitely.
After that, a good multi-threaded processor.
An SSD.
Graphics card and CPU are probably the most expensive and variable bits of the build.
CPU VS. GPU considerations
https://blender.stackexchange.com/questions/47598/should-i-buy-a-better-cpu-or-gpu
Also, be aware of the memory on the video card itself as that makes a huge difference once you get into larger scenes.
Good Luck!
Edit: You probably already know this, but if you’re building it yourself and not going the pre-built route make sure that your socket/processor/motherboard/memory, etc. all line up. Also, don’t skimp on the Power Supply, or a decent case with nice large fans for cooling!