Answer:
B) Some of their sons can have normal color vision.
Step-by-step explanation:
Some of their sons can have normal color vision. The normal vision mother must be a carrier and have one allele for colorblindness. The daughters would definitely receive the colorblind allele from their father, so there is no "might" about it. The daughters have a 50% chance of receiving the colorblind allele from their mother. The sons also have a 50% chance of receiving the colorblind allele from their mother. Since this allele is sex-linked and X-linked, the sons cannot receive the allele from their father.