Final answer:
The concordance values for a human characteristic entirely determined by genetics will be close to 100% for MZ twins as they share nearly all their DNA, and around 50% for DZ twins, who share roughly half of their genetic material.
Step-by-step explanation:
If we imagine that a human characteristic is determined solely by genotype with no environmental influence, we would expect different concordance values for MZ (monozygotic) and DZ (dizygotic) twins due to the amount of shared genetic information. Monozygotic twins are identical, having come from a single zygote that split, thus sharing nearly 100% of their genetic information. Dizygotic twins, however, are fraternal, and result from the fertilization of two separate eggs, each with its distinct genetic material, resulting in siblings that share about 50% of their genetic information, similar to non-twin siblings.
Therefore, the concordance values for a characteristic that is entirely determined by genetics would be close to 100% for MZ twins, since they have identical genotypes. If one twin has a particular genetic trait, it's almost certain the other will as well. For DZ twins, the concordance would be about 50%, the same as any two siblings, because they inherit different combinations of genes from their parents.
The correct answer to the student's question would be: c. The concordance values should be close to 100% for MZ twins and about 50% for DZ twins.