The answer would probably be be D
They come from crementation which is when disolved minerals are deposited in tiny spaces...
The answer I would choose is c
In the van deemter equation, plate height (H) = A + B/u+ Cu.
So, A, B, U, and C affects the plate height. A is the eddy diffusion term, B is the longitudinal or ordinary diffusion term, C is the nonequilibrium or resistance to mass transfer coefficient, and U is the linear velocity.
