Question 2 (1 point)

The identification problem would not prevent estimation of a demand curve from price and quantity data if, over the time period sampled, the only thing that varied was the ____ (Hint: which item(s) shift Demand Curves, which item(s) shift Supply Curves?)

Question 2 options:

a)	technology of production.

b)	level of consumer income.

c)	price(s) of substitutes and complements.

d)	level of advertising expenditures.