I understand that budgets may possibly not the same.
Ridiculous answer really in my opinion. If someone askes advice about lenses in the price range of $1000-1400 I would not suggest pro lenses i that cost well over $10.000.
Trying to answer OP's question
All three are ( for an enthusiast) very good lenses. Image quality will not differ much. Nikon 200-500 and Tamron 150-600 have the best shake reduction (VR). Nikon 200-500 has the best Auto fokus.
Sigma 150-600 C gives a lot of bang for the buck. Booth Sigma and Tamron has the advantage of having USB docks that makes it possible to upgrade firmware and fine tune AF at several focal lengths, handel shake reduction perfomance and more. Nikon 200-500 is the heaviest, Sigma the lightest. Nikon has the best (and most expensive) tele converter if you're interested in extending you reach.
I own the Sigma 150-600 C and Nikon 200-500. Satisfied with booth.
Hope that this may help in some way.