In this question no need to do any computation if and only if we carefully observe the prices of the 4 commodities.

Process of elimination :P

**Arhar**- The lowest pice of Arhar is greater than or Equal to that of Sugar.

**Pepper**- The lowest price of Pepper is much much greater than Arhar.

**Gold**(obviously costly :P )- The lowest price of Gold is Greater than that of Arhar.

**Sugar**- The highest Price of Sugar is less equal to the lowest price of Arhar.

But, on an Average the Sugar price is seemingly less than that of Arhar.

Hence, **(C.) Sugar is the answer.**