Which situation allows for evolution during gene duplication?
a. the original gene performs the same role as the mutated gene.
b. the original gene never duplicates.
c. a mutation occurs in one copy of the original gene.
d. existing genes are copied over generations.

answer; i do believe that the correct answer is; ///mendelian genes are at specific loci on the chromosome and, in turn, segregate during meiosis;

brain development. a child's brain undergoes an amazing period of development from birth to three—producing more than a million neural connections each second. the development of the brain is influenced by many factors, including a child's relationships, experiences and environment.

explanation: