Dorothea Dix is best known for her significant efforts in advocating for the rights and humane treatment of individuals with mental illnesses. The correct answer would be:
She documented abuses and advocated reform.
Dix conducted extensive investigations into the conditions of asylums and jails, documenting the inhumane treatment that individuals with mental illnesses faced. Her findings led to widespread reforms in the mental health care system, including the establishment of more humane treatment facilities.