What part of dna varies among dna molecules

Ineed to know why d is the correct answer asap

The allele for curly hair is incompletely dominant. if a mother is homozygous for curly hair and the father is homozygous for straight hair, what percentage of the offspring will exhibit characteristics of both parents? 25 percent 50 percent 75 percent 100 percent

Which of the following statements is accurate about evolution? question 10 options: natural selection only eliminates odd individuals. evolution means that a population never has changes in its genetic frequencies. mutations are always harmful. evolution means that a population undergoes changes in its gene frequencies over time.