Which of the following is a correct statement?

Decrease in input prices causes a leftward shift in the supply curve
The demand for a commodity is inversely related to the price of its substitutes
The desire for a commodity backed by ability and willingness to pay is demanded
When income increases demand for essential goods increases more than proportionately

The correct answer is: C. The desire for a commodity backed by ability and willingness to pay is demanded.

  • A. Decrease in input prices causes a leftward shift in the supply curve is incorrect. A decrease in input prices causes a rightward shift in the supply curve.
  • B. The demand for a commodity is inversely related to the price of its substitutes is incorrect. The demand for a commodity is inversely related to the price of its COMPLEMENTS.
  • D. When income increases demand for essential goods increases more than proportionately is incorrect. When income increases, the demand for normal goods increases, but not necessarily more than proportionately.

  • C. The desire for a commodity backed by ability and willingness to pay is demanded is correct. This is the definition of demand. Demand is the willingness and ability of buyers to purchase a good or service at various prices during a given period of time.