The correct option is A whole sale price index
Wholesale price index (WPI) refers to the average price of a representative basket of wholesale goods which includes prices of selective goods and services on the basis of which various market decisions are taken related to the supply of these goods and services.
In India, the general price level is measured on the basis of wholesale price index and all the central decisions are taken accordingly as it is the most idle index and includes all the relevant goods and services which is required and supplied in the economy.