Answer:
It is an example of how the environment alters the phenotype.
Explanation:
When referring to the phenotype, mention is made of the observable characteristics of each person. It should be taken into account that each phenotype will be different since it is based on the genotype of each person, and no person has the same.
But the phenotype is influenced by the environment, depending on the context it can undergo modifications, as is the case of the separated twins. Since each one had different nutrition, this had the effect of altering the phenotype, making each of them had a different development that would be significant for your tests.
I hope this information can help you.