Final answer:
The correct range for the function representing money in the college fund is from zero to infinity since there's no upper limit specified, which indicates the potential for indefinite growth through compound interest.
Step-by-step explanation:
The range for the function f(x) representing the amount of money in Samantha's college fund after x years cannot be less than zero because we cannot have a negative amount of money in a savings account. Since there is no given upper limit provided in the function, we infer the range of f(x) as the amount of money in the account can theoretically grow indefinitely through compound interest. Therefore, the correct option to fill in the blank (0≤f(x)≤________) would be c) f(x)≤[infinity].