Final answer:
A decrease in supply is reflected by a shift to the left of the supply curve, indicating that suppliers are willing to sell less at each price level.
Step-by-step explanation:
A decrease in supply is reflected by a shift to the left of the supply curve. So, the correct answer would be 1) Point A to Point B on the supply curve. When supply decreases, it means that at every given price, the quantity supplied is lower. This indicates that the suppliers are willing to sell less of the goods or services at each price level.