Under the feudal system, who owned the land (known as a fief) provided to a knight in exchange for money and loyalty?
a. caliph
b. serf
c. vassal
d. lord

the correct answer is “opportunity cost”. opportunity cost is what a company misses out because it decided in one option over another one. in this case, the company decided to invest in building a factory so it gave up another possible benefit or profit in order to achieve success with the factory.  

trade-off is not the correct answer since it is a situation in which you accept losing something in return for benefits in other areas.

and finally, consequence is a general term used to accept what it comes when you make a decision. it can be a positive or negative consequence depending if the decision you took was the correct one.  

d

explanation:

russia because it is the biggest state