A. Nutrients and other materials pass through the cell membrane through the process of diffusion. This allows the cell to perform all the activities it requires for daily maintenance and living. The concentration gradient allows the cell to regulate just how much of a certain material passes through it.
I believe it is B but I’m not 100% sure
Mutations. Definition. A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed.