Statement-I: "Quack therapies are scientifically unproven but potentially harmful." This statement is generally accepted as true. Quackery refers to dishonest practices and claims to have special knowledge and ability in some field, typically medicine. Such therapies lack scientific evidence of efficacy and can pose risks (harm) to individuals, especially if they lead to delaying or replacing proven treatments. Statement-II: "Stem cell therapy is a scientifically proven treatment for Autism." This statement is incorrect. As of current scientific understanding and medical consensus from major health organizations worldwide (like the FDA in the US, NHS in the UK, and various medical bodies globally), stem cell therapy is not a scientifically proven or approved treatment for Autism Spectrum Disorder. It is considered experimental, and many clinics offering it operate with questionable ethics and pose significant risks.