Read Each Paragraph and Place [Brackets] Around the Topic

Short Answer

Read each paragraph and place [brackets] around the topic.
-In the more than 50 years since the first successful organ transplant, hundreds of thousands of patients have had their lives extended because of organ donations.Despite decades of campaigns to persuade Americans to donate organs after they die, however,the demand increasingly exceeds the supply.The waiting list for organs, mostly kidneys,has doubled over the past decade to more than 92,000 patients.Eighteen die daily before getting one.
Carter, Mindscapes, 1st edition