the russian blue is a rare breed of cat that is susceptible to developing cataracts on the eyes. scientists hypothesize that this condition is inherited as a result of a mutation. figure 1 shows a pedigree obtained in a study of cats owned by members of the russian blue club in sweden.
a. A recessive mutation on the X chromosome
b.A recessive mutation on a somatic chromosome
c. A dominant mutation on the X chromosome
d.A dominant mutation on a somatic chromosome