Jason is selling video games. To earn his monthly bonus, he must sell a minimum of 5 games. He has 30 he can sell. The video games cost $20 each. The function f(x) = 20x can be used to represent this situation. What is the practical range of the function?

All whole numbers from 5 to 30, inclusive.


All whole numbers from 100 to 600, inclusive.


All real numbers.


All multiples of 20 between 100 and 600, inclusive.