Firms​ ________ in output markets and​ ________ in input markets.

A. ​demand; supply
B. ​demand; demand
C. ​supply; supply
D. ​supply; demand
Households​ ________ in output markets and​ ________ in input markets.

A. ​supply; demand
B. ​supply; supply
C. ​demand; supply
D. ​demand; demand