1990 से पहले भारत के व्यापार नीति ढांचे को सबसे सटीक रूप से इस प्रकार वर्णित किया जा सकता है:

Which institution maintains the buffer stocks of wheat and rice in India?

Consider the following statements regarding the Consumer Price Index (CPI) and its implications: I. The revised CPI aligns item weights with recent Household Consumption Expenditure Survey (HCES) data, better reflecting current consumption patterns. II. Under the revised index, services-related components (such as housing, health, education, and transport) carry a higher relative weight than earlier, improving the index's sensitivity to services inflation. III. A change in the CPI base year alters the measured inflation rate by itself, even if prices of all goods and services remain completely unchanged. IV. State-level inflation differentials under the revised CPI reflect differences in consumption structures in addition to food price movements. How many of the above statements are correct?