The red-green color blindness is a recessive X-linked trait. The females are not affected unless both the X chromosomes have the affected allele. Mostly, the females are the carriers, and the males are affected as they have only one X chromosome. In the given pedigree, the father of Irene have the normal allele, while her mother is a carrier. However, Irene is neither a carrier nor affected. This means that she carries normal alleles on both X chromosomes. Hence, her allele combination is 
.
Based on the given scenario, the best way to be used to
promote the safest movement of the patient is that the four rescuers present
should have each destined location on the patient where in, one of them should
be on the head, the other at the feet, and the two should be on each of the
side of the backboard.
Answer:
The correct answer is option D) six dominant and two recessive.
Explanation:
The most common genetic inheritance pattern involves cross between heterozygous recessive parents which means it has one allele of each character in every parent (suppose Tt).
Cross between these parents provide these offspring; TT, Tt, Tt, and tt which exhibit 3:1 ration which can also be mention as 6:2 which means 6 out of the 8 has dominant (homozygous or heterozygous) and 2 out of 8 offsprings are recessive alleles.
Thus, the correct answer is option D) six dominant and two recessive.
