Step-by-step explanation:
We are given that dimpled cheeks are dominant over un-dimpled cheeks , and two people with dimpled cheeks have a child without dimples .
For child to be born without dimples both of the parents should have one recessive allele.
- So the genotype of both the parents will be Dd ( D = gene responsible for dimpled cheeks ; d = gene responsible for un dimpled cheeks)
For cross between both the parents refer to the attachment.
- From the cross 3 offsprings out of 4 will have dimpled cheeks. Hence ;