The correct option is D It a sudden change in the genome of an organism, leading to gradual changes in the species
Mutations refer to sudden heritable changes occurring in the genome of an organism. Such changes could be a change in a single gene, or changes in the structure or number of one or a few chromosomes. Since this happens at the organism level, it would take many years to result in a change in the species. Mutation is hence, a sudden change in the genome, and inheritance of the mutation over the years would eventually and gradually result in evolution of the species.