The correct answer is sex linkage.
Sex linkage refers to the phenotypic expression of an allele, which relies upon the gender of an individual and is directly associated with the sex chromosomes. These genes are regarded sex-linked as their expression and patterns of inheritance vary between the males and females. The sex linkage cannot be the same as genetic linkage, the sex-linked genes can be associated genetically.
active transport. The movement of ions or molecules across a cell membrane in the direction opposite that of diffusion, that is, from an area of lower concentration to one of higher concentration. Active transport requires the assistance of a type of protein called a carrier protein, using energy supplied by ATP.
Answer:
2nd one is the most realistic of what occurs in ecosyystems
