The correct option is D 8
As a result of the mitotic division, the number of daughter cells becomes double. Thus, 8 mitotic cell divisions are required to produce 256 daughter cells from a single cell.
1. 1 x 2 = 2
2. 2 x 2 = 4
3. 4 x 2 = 8
4. 8 x 2 = 16
5. 16 x 2 = 32
6. 32 x 2 = 64
7. 64 x 2 = 128
8. 128 x 2 = 256
So 8 divisions are required to get 256 cells from one cell.