Final answer:
The three major groups of the SAR clade are Stramenopiles, Alveolates, and Rhizarians, which all contain members with chloroplasts derived through secondary endosymbiosis.
Step-by-step explanation:
The three major groups of the SAR clade are Stramenopiles, Alveolates, and Rhizarians. The SAR clade is a complex group of eukaryotes, which is found to be very diverse. It includes organisms that are photosynthetic and others that are important in the ecology of the oceans. One key characteristic of the SAR group is that they all contain members whose chloroplasts were derived by secondary endosymbiosis. These groups not only show variations in their photosynthetic capability but also show interesting variations in nuclear structure and modification of organelles such as mitochondria and chloroplasts.