What Does the Adage "There's No Such Thing as a Free

Multiple Choice

What does the adage "There's no such thing as a free lunch" mean?  

A)  Even people on welfare have to pay for food. 
B)  The cost of living is always increasing. 
C)  To get something we like, we usually have to give up another thing we like. 
D)  All costs are included in the price of a product.