If you count mining pools then you need 4 for BTC @QuipTalk

Answer: Yes, it is true that four mining pools are needed for BTC. This is because the mining process is incredibly competitive and requires a great deal of computing power. By joining a mining pool, miners can combine their computing power to increase their chances of successfully mining a block and earning rewards. The four major mining pools for BTC are AntPool, BTC.com, F2Pool, and SlushPool. Each pool has its own advantages and disadvantages, so miners should research each one before joining.

Ye just looked it up. Got even worse.