Atnswer:
b. lifecycle fund
Explanation:
as from now to 2050 are still remaining 31 years, the money invested is able to go under different risk profiles, looking for getting the maximun return, the lifecycle fund is an excellent choice, it is because this kind of strategies changes according the risk of its costumer changes. it is expected to have during the first years a high exposition to risk such as equity or derivatives, and the more age of the costumer the lower risk profile, so the closer to 2050 the more expected investment into low risk assets, such as fixed income (this is made for having the less losses possible)