Final Answer:
The organism expected to be found at level C in the ecological pyramid is c. Algae.
Step-by-step explanation:
In ecological pyramids, levels A, B, and C represent different trophic levels within an ecosystem. Trophic levels categorize organisms based on their position in the food chain. Algae, as primary producers, belong to the first trophic level (level A). They are responsible for converting sunlight into energy through photosynthesis. This energy is then passed on to the next trophic level, which typically consists of herbivores.
Considering the options provided, a. Cougar, b. Rabbit, and c. Algae, we can eliminate the first two options (a and b) because cougars and rabbits are typically consumers and belong to higher trophic levels. Now, comparing algae (option c) with d. Daisy, algae are primary producers and form the foundation of the food chain, making them the most likely organism to be found at level C.
To further support this, if we examine the energy transfer between trophic levels, only about 10% of energy is transferred from one level to the next. This phenomenon, known as the 10% rule, explains why there are fewer top predators (such as cougars) compared to primary producers like algae. The ecological pyramid reflects the energy flow within an ecosystem, with primary producers occupying the base, followed by herbivores and then carnivores. Therefore, the correct choice for level C is c. Algae.