Mining of bitcoins - because of "consumption of a huge amount of electricity and heated speculation with virtual currencies". This may include, in particular, the direct restriction of the supply of electricity to miners. In China, almost 80% of the world's mining capacities are located, and their closure can seriously affect the market of bitcoins.
true there could be a lot of currency also that are may affect if this may ever be happen , well we cant blame them they re having own decision and opinion for why is it can be happen and why they have to.