Which of the following can be considered a primary producer?

Flowering plants are classified as primary producers because they generate their own food through photosynthesis, a process that converts sunlight into chemical energy in the form of glucose. This process involves the use of chlorophyll in their leaves to capture sunlight, along with carbon dioxide from the atmosphere and water from the soil. As a result, flowering plants form the foundational level of the food chain, providing energy and nutrients for various herbivores, which, in turn, support higher trophic levels.

In contrast, rabbits and birds are consumers that rely on other organisms for food. Rabbits consume flowering plants, making them herbivores, while birds might also consume plants or insects, placing them in various consumer categories. Insects can also be herbivores (like caterpillars that eat plants) or omnivores, but they do not perform photosynthesis themselves. Thus, flowering plants uniquely qualify as primary producers within ecosystems.