I think that I would go with Bitcoin for sure because I have more experience with Bitcoin and not with gold but that is the only reason on why I should choose Bitcoin.
Maybe gold is also good and maybe even better then Bitcoin I do not even know.
Both are good in different manners as both of them has their own advantages and disadvantages, i'll tell one merit and one demerit of bitcoin and gold both, the best advantage of bitcoin is that it grows higher with the time which can generate someone quite a lot of profits if someone invests in it while the disadvantage of it is that it is not 100% safe as it is a digital currency and anything at anytime can happen with it.
On the other hand, the best quality of gold is that it is secure, nothing can happen to it as it has been around for centuries now and everyone believes blindly on it, but the thing about gold which can be considered as a disadvantage if you are an investor is that it does not grow in value as much as bitcoin does.