No one can tell you which portfolio will do better over the next 5 years.

Portfolio A is riskier so if the markets are kind, it'll do better than B. But the tradeoff is a higher likelihood that they could make nothing or even lose a little bit.

If they aren't sure what to do, they can split the difference and go with a 50/50 portfolio which would almost certainly not lose money in a 5-year time frame.