Why is the study of soil structure important?

a. relates to the chemical properties of soil
b. tell you how many nutrients are in the soil
c. is related to how well water and nutrients move through the soil

i would be so grateful if some one could me !

In sweet pea, gene c is responsible for color production and gene p is responsible for the purple color pigment. both of them are located on two different loci on different chromosomes. the flowers will be purple only when the plant has the genotypes as c_p_. no color will be produced with genotypes: ccpp, ccpp, ccpp, ccpp. thus, gene c controls the expression of gene p. what pattern of inheritance is exhibited here? a. pleiotropy b. epistasis c. multiple alleles