An economic model is a description of some features of the economic world that includes​ _____ features assumed necessary to explain the​ _____facts.
a. only​ those; observed
b. all​ the; observed
c. all​ the; unobserved
d. only​ those; unobserved
A) An economic model is a description of some features of the economic world that includes only those features assumed necessary to explain the observed facts, I think.
