Final answer:
Foods seasoned with salt substitute and frequent daily snacks of black licorice can decrease potassium levels, while prescribed potassium-sparing diuretics and occasional use of NSAIDs may not directly affect potassium levels.
Step-by-step explanation:
Potassium levels will be decreased by foods seasoned with salt substitute, as they often contain high levels of potassium. Consuming frequent daily snacks of black licorice can also decrease potassium levels as black licorice contains a compound called glycyrrhizin, which can cause excessive potassium loss. However, the use of prescribed potassium-sparing diuretics can actually increase potassium levels in the body. Occasional use of a non-steroidal anti-inflammatory drug (NSAID) may not directly decrease potassium levels.