The most logical answer that I can think from Darwin's Theory of Evolution is that that species had been isolated from other possible panthers to mate with. So after generations of that isolated group of panthers their offspring would eventually become increasingly similar.
C it will be c because earth has water
1.) Achodroplasia is a autosomal dominant disorder, the suspected case suggested that inorder for the parents to produce and offspring with achondroplasia. One parents must have a single mutant gene of achodroplasia to be inherited by his offspring. for this case, It is suggested that the offspring might have developed its own mutant gene as it only affect 1 in 25,000 birth. There is changes of genes during early development.
2.) The mother said that they don't have that history of disorder. again, it's autosomal dominant disorder. one parents must have that kind of disorder so their child can also inherit it. Thus, no of the childs parents is a carrier.
