We need to find the greatest interest in given options.
Let the principal amount be, P= $100.
The number of years, t =1
Consider the individual options.
a)
Simple interest,r = 5.0 % =0.05.
Consider the formula to find the simple interest.

Substitute P=100, r =0.05 and t=1 in the equation.


b).
Compound interest, r =5.0% =0.05.
n=4.
Consider the formula to find the compound interest.

Substitute n=4, P=100, r =0.05 and t=1 in the equation.


c).
Compound interest, r =5.0% =0.05.
n=12.
Consider the formula to find the compound interest.

Substitute n=12, P=100, r =0.05 and t=1 in the equation.


We know that


5.0% interest compounded monthly will return the greatest interest.
Final answer:
5.0% interest compounded monthly