Answer: The answer would be C
Explanation: This is because in order to express a recessive trait one must have no dominant alleles or otherwise the dominant would win out and be expressed instead. For example, if a person had 1 allele for brown hair and 1 for red the brown would win and the same would happen if they had 2 brown hair alleles. Whereas if a person had two alleles for red hair and none for brown, only then would the red trait be expressed. Hope this helped!