Answer:
Falling Incomes, due to a weakening economy
Explanation:
Falling in income would reduce the disposable income of consumers. Less income means consumers will be able to afford fewer goods (in this case, candles). As a result, demand for candles will reduce, resulting in a shift of demand curve to the left. As shown the diagram attached, Demand Curve for candles shifts to the left due to falling income, resulting in decline quatity demand from Q0 to Q1 and fall in price of candles from P0 to Q1
All others options are factors affecting supply of candles that will result in a shift of the supply curve.