The fourth alternative is correct (D).
This graph shows a decrease in the supply of graphic T-shirts. The chart demonstrates the supply of these shirts at each price level. The lines represent the supply curve. Initially the offer is the S line, orange color. In a secondary moment the supply curve shifts to the left, in the blue color (S1). In this curve, the supply is lower and prices are higher. For example, at the price of $ 17.50 30 shirts were provided on the first bid (S) curve. After the change, at the same price approximately 23 T-shirts are provided.
