Answer:
D
Step-by-step explanation:
The correct answer would be that the origin of all cells can be traced to previous or pre-existing cells.
According to the cell theory which is made up of three parts;
- The cell represents the basic unit of all life.
- All living organisms are made up of cells.
- Cells do not arise spontaneously, but only from pre-existing cells.
Hence, the discovery that the origin of all cells is traceable to previously existing cells supports the latter part of the cell theory.
The correct option is, therefore, D.