The long run is characterized by: Group of answer choices the relevance of the law of diminishing returns. at least one fixed input. insufficient time for firms to enter or leave the industry. the ability of the firm to change its plant size.

D. The ability of the firm to change its plant size.

Explanation:

The long run in economics is a period of time in which all inputs in the production process can be varied. It allows firms to have the ability to change its plant size that would be more or less fixed in the short run. The factors of production used in the long run are variable inputs. Variable inputs are inputs that can be change or altered in a production system. The firm in the long run has the abilities to respond to changes in the market and demand and can build bigger factory or larger plants.