The right answer is the third one: the bubonic plague originated in the Gobi Desert, part of the then Mongol Empire, around 1320. It then propagated to China and subsequently to India, Europe and Russia. The disease spread via trade routes mainly as a result of a poor hygiene. It never reached the American continent or Sub-Saharan Africa.
The Russian Revolution happened in 1917
So the answer is Russia
Answer: property taxes and business license fees
Explanation: those are all large sources of income but what I said are probably the biggest assuming you talking about the USA.