If total expenditures in the economy are greater than total production:

a$)$ inventories will decrease, which signals firms that they have under$-$produced and thus should increase production.

b$)$ inventories will increase, which signals firms that they have overproduced and thus should cut back production.

c$)$ inventories will decrease, which signals firms that they have overproduced and thus should cut back production.

d$)$ inventories will increase, which signals firms that they have under$-$produced and thus should increase production.