Answer:
C. All living things are made up of at least one cell.
Step-by-step explanation:
A cell is a structure formed of carbon-based molecules with the cytoplasm inside the membrane which contains the bio-molecules needed to survive like the proteins, DNA, enzymes, and others.
The structures when studied by the Schelidnen in plant cells and Schwann in animal cells concluded that the living organisms are composed of the cells and cell is the smallest unit of life as it is the functional and structural unit of life and formulated the cell theory.
Since all living organisms are composed of the cell, therefore, Option-C is the correct answer.