The law of segregation comes from the fact that each gamete gets only one copy of each chromosome and, thus, one copy of each gene on each chromosome. The two copies physically segregate in anaphase I. The fact that genes are usually far apart on one chromosome (many crossing over events around metaphase I) or on physically separate chromosomes leads to the law of independent assortment.
Work Step by Step
This question asks you to review and connect the events of meiosis and the data obtained by Mendel to see how the abstract genetic principles match up with the physical movement of DNA pieces.