What is the relationship between the carbon cycle, photosynthesis, and cellular respiration in an ecosystem

Respiration and photosynthesis are both related to the production/release of carbon dioxide.

Explanation:

Plants and trees use photosynthesis to use carbon dioxide in the air,water and sunlight to produce glucose and oxygen.Equation for photosynthesis:  

Carbon dioxide + water + light energy = glucose + oxygen

Respiration is process of breaking down to give off energy. It is used by animals.Plants also respire but only there is a lack of sunlight.Respiration uses oxygen and breaks down to produce energy,water and gives off carbon dioxide as a byproduct.Equation:

Glucose + oxygen = water+carbon dioxide + ATP

Photosynthesis therefore reduces carbon dioxide while respiration adds to levels of carbon dioxide.That is their relation to the carbon dioxide

the answer is d (apex) good luck : ))