Experiments are often replicated or repeated even when no obvious mistake was visible. This is to establish how variable results are. Statistically, multiple runs are used to determine the variance or standard deviation around the average value. The best answer for this is choice C, to double check results.
I think what happens is that the Cyclin component of the MPF is degraded. MPF or mitosis promoting factor, consists of two important cell cycle regulatory protein called the cyclin and cyclin dependent kinases (CDK). The cdk and the cyclins are the major control switches for the cell cycle, causing the cell to move from G1 to S or G2 to M.
Diffusion occurs because of the movement of molecules from
the region of higher concentration to the region of lower concentration. This
movement of molecules occurs due to a thermal motion. Diffusion normally occurs
between two compartments having difference in concentration. In case of fluid
it moves from the region of higher concentration to the region of concentration
until a balance is reached. The process of diffusion is very important for the
humans as well. The oxygen that humans breathe in gets diffused with the blood.
