Final answer:
The phase of the business cycle where businesses appear to be highly profitable is called the boom phase. During this time, the economy is flourishing, leading to increased business activities and profits.
Step-by-step explanation:
The business cycle is an essential concept in understanding economic fluctuations and consists of four phases: expansion (or boom), peak, contraction (or recession), and trough. When asked which phase of the business cycle most businesses appear to be highly profitable, the answer is the boom phase. During a boom, the economy is flourishing; businesses typically experience increased sales, higher production rates, and more substantial profits. This is the opposite of a recession, which is marked by a contraction in economic activity, and the trough, which is the lowest point before the economy begins to recover.
The longest period of expansion in the twentieth century started after the Great Recession's trough in June 2009 and had a significant duration until the COVID-19 pandemic-induced recession in February 2020. Therefore, to the given options (a) Trough, (b) Recession, (c) Recovery, (d) Boom, the answer is (d) Boom.