The correct answer is a) autotrophic. Autotrophic organisms are capable of producing their own food using sunlight or inorganic substances. This process often involves photosynthesis or chemosynthesis, allowing them to convert light energy or chemical energy into organic compounds.
In contrast, heterotrophic organisms cannot produce their own food and must obtain energy by consuming other living things. The terms oxidative and chemiosmotic do not directly relate to the ability of an organism to produce food; rather, they describe processes involved in energy production and metabolic pathways.