Correct Option (d)
A rise in the general level of prices, commonly known as inflation, can be caused by various factors related to demand and supply dynamics in an economy.
- An increase in the money supply: When the quantity of money circulating in an economy rises without a corresponding increase in the production of goods and services, there is more money available to purchase the same amount of goods. This increased purchasing power leads to higher demand, which in turn pushes up prices (demand-pull inflation).
- A decrease in the aggregate level of output: A reduction in the total supply of goods and services available in the economy, while demand remains constant or increases, creates scarcity. This imbalance between reduced supply and existing demand leads to an upward pressure on prices (cost-push or supply-side inflation).
- An increase in the effective demand: Effective demand refers to the desire for goods and services backed by the ability to pay for them. When there is a significant increase in the overall demand for goods and services across the economy, and this demand is not met by an equivalent increase in supply, sellers can raise prices, leading to a general rise in the price level (demand-pull inflation).
Since all three statements accurately describe conditions that can lead to a rise in the general level of prices, option (d) is the correct answer.
Incorrect Options:
Options (a), (b), and (c) are incorrect because they only partially identify the causes of a rise in the general level of prices. Each of the three statements provided in the question represents a valid and distinct mechanism through which inflation can occur. Therefore, an answer that includes all three statements is necessary for a complete explanation.