Final Answer:
This text is an example of an expository piece because it focuses on presenting factual information about an amazing medical breakthrough without attempting to persuade, narrate, or describe.
Step-by-step explanation:
Expository writing aims to inform or explain a topic in a clear, concise, and objective manner. In this case, the text likely discusses the details of a groundbreaking medical discovery, providing factual information, such as how it works, its potential impact on healthcare, and its significance in the field.
Correct answer: Expository.