Final answer:
The fluctuations along a country's GDP line are known as 'business cycles'. These are periods of economic expansion and contraction which do not follow a predictable pattern but are essential for economic prediction.
Step-by-step explanation:
Fluctuations along a country's GDP line are known as business cycles. Option B, Business cycle, is the correct answer to the question. A business cycle is a period of macroeconomic expansion followed by a period of macroeconomic contraction. These fluctuations in the market occur around a long-term growth trend and involve shifts between periods of rapid economic growth and periods of stagnation or decline. These changes in real gross domestic product (GDP) do not follow a predictable pattern, which makes the understanding of business cycles crucial for economic forecasting.
The strong>four phastrong ses of the business cycle are expansion or boom, peak, contraction or recession, and trough. Over time, strong>real GDP tends to increase, but not evenly, reflecting these cycles. A significant decline in GDP characterizes a recession, which begins at the peak and ends at the trough of a business cycle. A more prolonged and severe downturn is termed a depression.