The correct answer is: A. general price index.
A general price index is a measure of the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services. The most common type of price index is the consumer price index (CPI), which measures the prices paid by urban consumers for a market basket of consumer goods and services. The CPI is used to track inflation, which is the rate at which prices for goods and services are rising.
A special price index is a measure of the average change over time in the prices paid by a specific group of consumers for a market basket of goods and services. Special price indexes are often used to track the prices of specific goods or services, such as housing or medical care.
A monetary value index is a measure of the average change over time in the prices of goods and services, expressed in monetary terms. Monetary value indexes are often used to track the purchasing power of money.
A discount factor index is a measure of the average change over time in the present value of a future sum of money. Discount factor indexes are often used to track the time value of money.
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