Please answer the following question: Given the following passage  "There are special rules for certain rare diseases ("orphan diseases") in several major drug regulatory territories. For example, diseases involving fewer than 200,000 patients in the United States, or larger populations in certain circumstances are subject to the Orphan Drug Act.  Because medical research and development of drugs to treat such diseases is financially disadvantageous, companies that do so are rewarded with tax reductions, fee waivers, and market exclusivity on that drug for a limited time (seven years), regardless of whether the drug is protected by patents.",  answer the following question. Note that the answer is present within the text.  Question: Which of the following is a benefit granted by the Orphan Drug Act: patents, fee waivers, or medical research?
A:
fee waivers