Final answer:
Trees are autotrophs, they can produce their own food through photosynthesis.
Step-by-step explanation:
An autotroph is an organism that can produce its own food using energy from the sun or other inorganic substances. Out of the given options, the best answer is b. tree. Trees are autotrophs because they undergo photosynthesis, using sunlight to convert carbon dioxide and water into glucose and release oxygen.
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