The correct answer is Plant because plants are autotrophs that produce their own food through photosynthesis, using sunlight, carbon dioxide, and water. This process allows them to convert inorganic substances into organic nutrients, which supports their growth and energy needs. In contrast, fungi, humans, and dogs are heterotrophs that rely on consuming other organisms or organic matter for energy. Understanding autotrophy is key in fields like nutrition and metabolism.

Reference: Biology, Campbell and Reece, 10th Edition.