I like the strategy C. Long-term holding
But, what if when we need the money and the coins we hold have not reached the target?
that is why we only need to invest the amount that we can afford to lose, because investing for long term really needs time and patience to have a bigger profit in the end.
This is a reasonable piece of advice. The only problem is an amount of money that is affordable to lose almost always would be too small to make a difference. Nobody wants to lose any amount of money. You have to take risks to have a chance to earn a significant amount of money.