Final answer:
An increase in the price of car washing equipment would cause a leftward shift in the supply curve for car washes, as it would raise production costs, leading providers to supply less at all price levels.
Step-by-step explanation:
To determine which factor would cause a leftward shift in the supply curve for car washes, we need to consider how various changes affect the supply. A leftward shift implies that less of a service is provided at every price level. Looking at the options provided:
- An increase in the number of cars in the city (Option A) would likely lead to an increased demand for car washes, not a shift in the supply curve.
- A decrease in taxes on car washes (Option B) would reduce costs for providers, which typically leads to a rightward shift in the supply curve.
- An increase in the price of car washing equipment (Option C) represents an increase in production costs, which would reduce the profitability of car washes at current prices, leading to a leftward shift in the supply curve of car washes as providers are willing to supply less at every price level.
- A decrease in the price of water (Option D) would lower a key cost, thus likely shifting the supply curve to the right, as it would be cheaper to provide car washes.
Therefore, the correct answer is Option C: An increase in the price of car washing equipment.