The correct answer is B) vapor recovery. Vapor recovery is the recommended procedure to minimize the loss of oil during the recovery of refrigerant from small appliances like a water cooler. This is because the vapor phase of the refrigerant typically contains less oil than the liquid phase. By recovering the refrigerant in the vapor state, the amount of oil lost from the system is minimized. The other options are not as effective for this purpose. Initial recovery (A) does not specifically target minimizing oil loss. Liquid recovery (C) is more likely to result in oil being recovered along with the refrigerant. Vapor-liquid recovery (D) is a more complex process that is not necessary for small appliances.