Pandita Ramabai, author of The High Caste Hindu Woman and an early feminist and social reformer, converted to Christianity and went on to found the Mukti Mission.
It isn’t completely clear in this picture, but Helen Dyer records in her biography of Ramabai that she chose to retain Indian dress. Lakshmibai Tilak, also records that Indian Christian women chose to adopt the pleated sari and blouses with wrist length sleeves and kept ornaments to a minimum.
PS: Ramabai also wrote an account of her visit to the US, which is now available in an English translation.