What is the primary source of energy for living organisms on Earth?a) Chemical energyb) Solar energyc) Geothermal energyd) Nuclear energy

The primary source of energy for living organisms on Earth is b) Solar energy.

Detailed Explanation:

1. Photosynthesis: Most life forms, especially plants, utilize solar energy through the process of photosynthesis. During this process, they convert sunlight into chemical energy in the form of glucose, which serves as food for the plants themselves and, indirectly, for herbivores and the entire food chain.

2. Food Chain Dependency: The solar energy captured by plants forms the basis of the food chain. Herbivores consume plants to obtain energy, and carnivores eat herbivores.

3. Alternative Energy Sources: While chemical energy (in the form of food), geothermal energy, and nuclear energy can contribute to specific ecological processes or human activities, they are not the primary sources for sustaining the overall biological energy needs of life on Earth.

Thus, solar energy is crucial as it directly influences the energy flow within ecosystems.