Answer:
see below
Explanation:
The problem statement seems to presume you have seen an exponential function like this written as ...
f(t) = a0·(1 +r)^t
where a0 is the value corresponding to f(0) and "r" is the fractional rate at which the value increases for each increment of t.
Here, 1+r corresponds to 1.04 in the given function, so r = 0.04 = 4%. When the value is greater than 0, it means there is an increase by that fraction each time t increases by 1.
Here, t is not defined, either, but it would usually be used to represent years in a situation like this. (In other situations, it might represent months, hours, or millenia.)
Hence, the appropriate choice is the one that describes a 4% annual increase.