There are many answers to your questions, so here is my suggestion to your question. If you are not a trader and you are just a normal investors who put his money to bitcoin in hoping to get some profits in the long run then holding is your best option.

But if you are trader and you already earn some profits from the past increase of bitcoin price then it is the right time to cut your losses and sell your assets then wait for the right time to buy again. As this dips will surely to go down for sure and once you can hit the bottom of the dips then you can surely profit a  good amount of money once the bitcoin price will start to rally again upward.