Which one of the following statements is the most accurate with respect to the concept of time value of money?

a$.$ The time value of money is indifferent to the use of discount rates.

b$.$ I will gladly pay you Tuesday for a Hamburger Today.

c$.$ The time value of money gets weaker the longer the time period being considered.

d$.$ One would be indifferent between receiving $$1$ today or receiving $$1$ tomorrow.