The correct answer to this open question is the following.
Although there are no options attached we can answer the following.
His travels in Goa, India, led him to use plants for medicine, including what, used to treat malaria.
Here, we are talking about Portuguese herbalist and physician García de Orta.
García de Orta (1501-1568) did deep research for that time to discover how to treat malaria and other diseases. He was one of the first physicians to develop research on tropical medicine and used ethnobotany to help people in Goa, India.
He had to do much experimentation with plants of the region, He thought that would better than traditional medicine that had already shown its limitation to treat tropical diseases.
He also had the time to write a book titled "Magnus Opus," in 1953, in which he referred to the use of herbal medicine and its benefits.