In lines 13-15 we are told that in a specific bacteria, there are enzymes that synthesize and break down rigid cell walls in order to help the bacteria's growth. However, if someone removes the cell wall from one bacterium, the bacterium will continue to grow and multiply indefinitely without walls, (lines 15-20). Thus, from removing the cell wall of one bacterium, the rest of the bacteria that result from it could have an absence of cell walls, i.e. answer choice (C): "It can be caused by the loss of a cell wall in a single bacterium."
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