• Photoautotrophy:
• Organisms that utilize solar radiant energy to synthesize organic compounds from inorganic carbon dioxide ($CO_2$):
• Oxygenic Photoautotrophs: Cyanobacteria, green algae, and higher plants (use $H_2O$ as electron donor, releasing $O_2$).
• Anoxygenic Photoautotrophs: Green sulfur/non-sulfur bacteria and Purple sulfur/non-sulfur bacteria (use $H_2S$ or organic molecules as electron donors, without generating $O_2$).
• Fungi are non-photosynthetic, heterotrophic chemoorganotrophs.
• nalysis:
• (Green bacteria, purple bacteria, cyanobacteria and algae): Correct list of photoautotrophs.

Correct option: (4) Green bacteria, purple bacteria, cyanobacteria and algae