Everything in crypto is risky.If i had to pick just one alt,i would pick something strong on thr market.Yes profit might not be as good as low market cap coin,but risk of scam will be a lot lower
Being in only 1 coin is risky. If you're in bitcoin and ethereum, it's more safe but still risky. Having more coins is more logical in this situation. If one drops down, the others can rise up by giving you profit.