Answer:
(B) the macroeconomy
Step-by-step explanation:
The condition of the macroeconomy would exert the most influence of a firm's decision to hire more workers. As economic growth increases and demand grows, the firm is likely to hire more workers to meet increasing demand for its goods. On the other hand, in an economic recession, the firm is likely to hire less and even lay off its existing workers as demand for its goods reduces.
Option A is incorrect as a firm would not hire more workers even at low wage levels if the economy is in a recession. Option C is incorrect as the level of a firm's income would likely not be considered in its hiring decision if demand for its goods was very high. Option D is incorrect as the household income would likely not be considered by the firm in its hiring decision.