These ciliates are Alveolates, placing them in the SAR clade. Endosymbiosis gave them their mitochondria, but not plastids, which they lack. They are more closely related to some other protists (those in the SAR clade, especially on the Alveolate branch of that clade), but not to all other protists compared to plants, animals, and fungi since those multicellular eukaryotes are found on other branches of the tree of life including other protists.
Work Step by Step
The key figure is the olive-colored box on p.595 and remembering that relatedness involves branches. Also recall that the protists are a polyphyletic group spread across the lower parts of the phylogenetic tree including all organisms, making it hard to say to what all of them are closely or distantly related.