The choice also depends on the amount of capital each investor has. You can invest in BTC or ETH if you're an investor with a large capital, as that's a safer choice. However, personally, I choose to invest in ARB because my capital is not very large, and ARB is a relatively safe option.
ETH is certainly relatively safe for me even though the capital is quite small.
Just choose the best besides Bitcoin and ETH will be number two. ARB might be an option for my backup investment. There are still many choices of coins for investment, especially BNB, which also have long-term potential. Especially those who have a lot of BNB will always have the opportunity to join the Launchpad on binance. The more BNB you hold, the higher the allocation you will get.