Answer: 1. Algae, 2. Plants, 4. Some bacteria and 6. Protists are photosynthetic autotrophs.
Photosynthetic autotrophs are defined as the organisms that prepare there own food in the presence of sunlight through photosynthesis.
It is the mode of nutrition of all plants, algae, some protistans and some bacteria that use the energy obtained from sunlight to form glucose in the presence of carbon dioxide and water.
Examples of photoautotrophs are Kelp which is an algae, Euglena which is a protist, Cyanobacteria which is a bacteria.
Therefore, the correct options are “1. Algae, 2. Plants, 4. Some bacteria and 6. Protists”