Final answer:
Yeast is not an autotroph, while grass, O algae, cyanobacterium, and the oak tree are autotrophs.
Step-by-step explanation:
The autotrophs are organisms that can produce their own food using energy from sunlight or inorganic substances. Yeast is not an autotroph because it cannot produce its own food and relies on organic substances for nutrition. Grass, O algae, cyanobacterium, and the oak tree are all examples of autotrophs because they can perform photosynthesis or other forms of autotrophic nutrition.
Learn more about Autotrophs and non-autotrophs