Energy from sunlight is being used in an indirect way for walking the dog. Plants photosynthesize in which they absorb energy from sun and convert it into chemical energy, which is stored in organic product formed as a result of photosynthesis. When this organic compound is consumed by us, we use the chemical energy stored in that food to mechanical energy for walking the dog. Hence, the energy to walk the dog comes from sunlight.
I believe it was just called "the rule of law"
I think that the answer is d
