Concept:Mendel’s first law states that alleles separate during gamete formation, so each gamete receives only one allele from a pair.
Explanation:When pure tall plants are crossed with pure short plants, the F1 offspring are all tall.
These F1 plants carry one tall allele and one short allele.
During gamete formation, the two alleles segregate from each other.
This segregation is observed because the short trait reappears in the next generation.
Thus, segregation of genes is best demonstrated in a cross between tall plants and short plants, which produces hybrids showing allele separation.
Answer:C. tall plants and short plants are crossbred