I think each has its advantages and disadvantages, it is for different types of people. If you are a safe trender, you are afraid to risk, you should choose gold and USD. Because it seems its price is quite stable and safe. But it will not help you earn a lot of money after a period of investment. On the contrary, those who like adventure and bravery should choose BTC. It will help you become rich or not lose in a short time. For me, I always choose BTC because I like adventure