In bacteria, many transposable elements are able to regulate their own transposition in such a way that the probability of transposition decreases as the number of copies of the transposon in a cell increases. If a transposon invades a bacterial cell that does not currently have any transposons, and then increases in copy number as the cell divides, what curve below would BEST depict the increase in copy number of such a self-regulating transposon?