Selectivity permeable membrane and a scaffold for biochemical activity
For each of the examples, simple diffusion, carrier, and channel mediated, each type involves the flow down a concentration gradient. This means that the molecules flow from an area of high concentration to an area of low concentration. In turn, this allows for a passive process, meaning no ATP is needed! I hope this explains your question.
It is a case of CODOMINANCE where the two alleles are expressed
I belive the answer is d.
