Final answer:
Protists capable of both photosynthesis and absorbing nutrients from dead organisms are known as mixotrophs, with euglenoids and dinoflagellates as examples.
Correct option is c) Mixotrophs
Step-by-step explanation:
Protists with the capabilities to perform photosynthesis and to absorb nutrients from dead organisms are called mixotrophs. This unique mixotrophic nutrition can be found in groups such as euglenoids and dinoflagellates. For example, the genus Euglena includes species that are photosynthetic when light is available, using chloroplasts they obtained through secondary endosymbiosis from green algae. However, in the dark, these chloroplasts cease functioning, and the Euglena can absorb organic nutrients from the environment as a heterotroph.
Dinoflagellates, on the other hand, contribute to symbiotic relationships as seen in coral reefs, where they provide essential nutrients for coral polyps while living in their protected environment.