Assume that Figure \( 4-16 \) shows the supply of soda. An increase in the price of syrup used in the production of soda will shift supply from a. \( \mathrm{S}_{1} \) to \( \mathrm{S}_{2} \). b. \( \mathrm{S}_{1} \) to \( \mathrm{S}_{3} \). c. \( \mathrm{S}_{2} \) to \( \mathrm{S}_{3} \). d. \( \mathrm{S}_{2} \) to \( \mathrm{S}_{1} \).

When the price of syrup, a key input in soda production, increases, it raises the cost of making soda. This causes producers to supply less at any given price, shifting the supply curve to the left. So, if we assume that \( \mathrm{S}_{1} \) represents the initial supply curve, the correct answer would be option a: \( \mathrm{S}_{1} \) to \( \mathrm{S}_{2} \). The intuition behind this is straightforward: as production becomes more expensive due to higher input costs, suppliers are less willing to produce the same amount of soda at previous prices, leading to a decrease in supply. The leftward shift of the supply curve reflects this change in production costs.