If you want to get high profits and are willing to take risks, I suggest choosing altcoins,
but if you don't want to take risks, then my advice is to choose bitcoin,
because bitcoin is still very safe for investment.
Not only in altcoins, but we also can get high profits by investing in Bitcoin. But surely we need a bigger capital when we invest in Bitcoin. We can't expect to get big profits if we only invest $100 in Bitcoin. You can expect earning of thousands dollars if you invest in Bitcoin above $1000 as well. So, basically, the amount of money to get depends on how much capital we used in our investments.
Anyway, investing in Bitcoin doesn't mean to have no risks.