Answer:
D.

Step-by-step explanation:
We have been given that Franklin deposits $3500 in an account that earns 3.5% interest compounded annually.
Since amount is increasing exponentially, so we will use exponential function to write the formula for our function.
Since an exponential function is in form:
, where,
a = Initial amount,
b = For growth b is in form (1+r), where r represents growth rate in decimal form.
Let us convert our given rate in decimal form.

Upon substituting our given values in exponential function formula we will get,

, where, f(t) represents total balance in the account after t years.
Therefore, the function
represents the balance of the account after t years and option D is the correct choice.