Question

what is the source of all living things?

Explanation:

In biology, cells are considered the basic unit of life and can be seen as a fundamental source - all living things are made of cells or are cellular in nature. Also, in an ecological and evolutionary context, the sun provides the energy that drives life on Earth through processes like photosynthesis which is the basis for food chains and the sustenance of life. But at a more fundamental biological level, cells are key.

Answer:

Cells