Answer:
C. consumer price index
Step-by-step explanation:
The consumer price index CPI is the index used in the USA to measure inflation. The CPI calculates changes in the weighted average prices of a basket of goods and services representing consumer expenditure in the economy. The average change in prices computed in the CPI communicates the rate of inflation.
Inflation is the average change in prices in the economy in time. The CPI measures the changes in the weighted average prices of a basket of goods and services representative of consumer spending. Therefore, the CPI measures the rate of inflation.