Bitcoin, as it is the most popular and always at the hearing, is more likely to benefit by investing in this currency.
I don't think this is a good ideal at all, Bitcoin is no more the most promising crypto to invest anymore at the moment that it was going down from 20k$ to 8k$. Everthing isn't that smooth for Bitcoin.
Still we all believe it will recover and rise up eventually. So investing in BTC is a good advice. But there are a lot of other coins you can invest ETH, EOS, NEO and so on.