Final answer:
Most primary producers make their food through photosynthesis by using light energy to create carbohydrates. Photosynthesis converts CO2 and water into glucose and oxygen, while cellular respiration breaks down carbohydrates for energy, releasing CO2 and water.
Step-by-step explanation:
The majority of primary producers, like plants and certain bacteria, synthesize their own food through the process of photosynthesis. This process involves capturing light energy from the sun and converting it into chemical energy, which is stored in the bonds of carbohydrates such as glucose. More specifically, during photosynthesis, carbon dioxide (CO2) and water (H2O) combine with sunlight, resulting in the production of carbohydrates and the release of oxygen.
Therefore, the correct option for how most primary producers make their own food is:
c. by using light energy to make carbohydrates
Additionally, primary producers and all organisms perform cellular respiration, a process that breaks down carbohydrates to release the energy needed for life functions. During cellular respiration, carbon dioxide and water are produced as byproducts, and these substances are subsequently used in photosynthesis, completing the energy cycle.