The property that is shared by the cells of all living things is:
The cells contain DNA composed of adenine, thymine, guanine, and cytosine.
This characteristic is fundamental to all living organisms, as DNA is the hereditary material that carries genetic information necessary for growth, development, and functioning. Other options, such as reliance on mitochondria or the presence of a cell wall, are specific to certain types of cells (e.g., plant cells) and not universally applicable to all living cells.