I purchased it $24 but do i must hold or, sell it and buy another?
I also think if btc go to hell, than china money would be invested in Monero, because their money is black money.
what do you think?
Well, buying it for $24 was too much. Now monero is decreasing in price, but I think it is better for you to hold and hope for something good. There aren't many people who think Monero is a completely useless coin, it can solve some problems other currencies can't. Like security issues, as was stated above in this thread. I personally see nothing attractive in Monero but admit that the currency deserves better than it has now.
In March of this year, they discussed whether to buy Minero for $ 24. Now his rate is 129 dollars with a capitalization of about two billion dollars. The conclusion is unambiguous, it was necessary to buy.