Best CCurency?

I don't think you're asking the correct question, what are you trying to do? purchase crypto or mine it?

If you're mining the question isn't simple because the price fluctuates a lot one day could be bitcoin next day ether. The best thing to do is look at what the prices are, and how difficult is it to mine each type of coin. some are easier than others which is why they're not worth as much. There's no simple answer best to do your own research as it's not the same answer for everyone NinjaBear is on the right lines those are good choices but the choices will always change