Alpha Test biology genetic question

Hi, for this question I chose B and the correct answer is E. I don’t know how to rule out each option at all. Please somebody help me.

10
Which of the following could explain why the phenotype of a healthy female child may show differences from her healthy biological brother (apart from the gender)?

  1. Independent assortment after the formation of the female zygote
  2. Crossing over between a chromosome from the sperm and a chromosome from the egg
  3. Random alignment of homologous chromosomes at the equator of the cell during
    metaphase I
    A 1 only
    B 1 and 2 only
    C 2 and 3 only
    D 2 only
    E 3 only