Dr Lim Identified Three Independent Variables of Interest: Hair Color

Dr. Lim identified three independent variables of interest: hair color, career, and eye color. Dr. Lim decided to only use red-haired and blond-haired participants, as well as only doctors, lawyers, and politicians in his study. He also was only interested in hazel-, blue-, and green-eyed individuals. What type of factorial design does that describe?

A) 2 × 2
B) 2 × 4
C) 2 × 3 × 4
D) 2 × 3 × 3