<span>Cilia projections from cell surfaces that aid in locomotion and feeding; also used to sweep substances along surface, as well has flagella which is a tail-like projection that aids in locomotion</span>
Answer:
D
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;
- <em>The cell represents the basic unit of all life.</em>
- <em>All living organisms are made up of cells.</em>
- <em>Cells do not arise spontaneously, but only from pre-existing cells.</em>
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.