Just a noob's thought and some advice...

Lets say that exchange A has a buy order for 99Euros and exchange B has Sell orders at 101Euros.
If someone buy from A and then makes it to sell at 101 on B, what would be better to do, having earned the 2 dollars profit?

1) Cash out from exchange B?
2) Exchange the fiat total amount for an altcoin and exchange back to btc?
3) Do nothing and wait for prices to drop below than the previous buy and do afull cycle again?
4) Something else?