Which organism would most likely be the main sourceof oxygen in a forest ecosystem? a. ants b. lichens c. oak trees**** d. mushrooms

yes. Odd forest with just those four plants.

that is not an answer. The answer is "B''

To determine the main source of oxygen in a forest ecosystem, we need to think about the process of photosynthesis. Photosynthesis is the process by which plants and some other organisms convert sunlight, carbon dioxide, and water into oxygen and glucose (a type of sugar).

Considering this, we can eliminate options (a) ants and (d) mushrooms, as they are not capable of photosynthesis.

Now, let's compare options (b) lichens and (c) oak trees. Lichens are symbiotic organisms consisting of a fungus and either algae or cyanobacteria. While they can contribute to oxygen production, their overall contribution is typically limited due to their smaller size and relatively slower rate of photosynthesis.

On the other hand, oak trees are large, long-living trees that have a significant capacity for photosynthesis. They possess a substantial number of leaves, which are the primary sites of photosynthesis, and can produce a considerable amount of oxygen.

Therefore, the most likely main source of oxygen in a forest ecosystem is option (c) oak trees.