Question

what is the primary source of energy in a food chain?
○ oxygen
○ sun
○ carbon dioxide
○ water

Explanation:

In a food chain, the primary source of energy is the sun. Producers (like plants) use sunlight to perform photosynthesis, converting solar energy into chemical energy stored in food. Oxygen, carbon dioxide, and water are involved in photosynthesis or respiration but are not the primary energy source.

Answer:

B. sun (assuming the second option is labeled as B; if the original options had labels like A, B, C, D with "sun" as the second, the answer is the option with "sun"—e.g., if the options are A. oxygen, B. sun, C. carbon dioxide, D. water, then the answer is B. sun)