Great question: Ethereum is a solid guess, since it is (ideologically and as a platform) backed up by large entities. However I'd say, that first coin to bounce back will most probably be Bitcoin. BTC itself is a solid indicator of crypto market mood. Check charts and see, that BTC long term gain (we are talking in months) does fuel rest of crypto market. Be it cross-sell, speculation, moving assets around and so. BTC rise is followed by other altcoins and vice versa. The only exception to this are cases of low short (days) term dips, where money just circulates among various cryptos. This can be spotted by total market cap not really changing. It is not so this time. So I'd say first will be BTC, then others.

Warning: this is not a trading advice and I am not taking any responsibility for your loss :)