When you choose the high risk there is a chance to lose or gain 100% of your investment (Medium is 75% and low is 50% if I remember it right). It doesn't make sense to me, it sounds like a scam, they will invest using your money and you don't have any control to it. That is why I like bitcoin more, coz Though it is risky and it's very volatile, you have full control on your investment.
So they call a 50% possibility to lose your funds a "MEDIUM" level of risk?? That's indeed stupid, you have a bigger chance to win even playing cards!!
In general, bank investment is less risky, but that's if compared with European, American and Canadian banks.
So if I were you, I wouldn't accept any of those plans proposed by your banks and invest in bitcoin.