The evolution of the two species are very closely related but not identical
B) Physiological because C is relating to the inside of the organism, A is relating to the forming part of a building or another item and D is reacting to their physical surroundings, so the only other answer would have to be B because in physiological in animals and humans alike, they change something of their physical self's to attain to the environment around them.
The operon is effectively the center of transcriptional control. In addition to its main structural genes, the operon houses an operator and a promoter. In front of the promoter lies a regulatory gene that produces repressor proteins. When a repressor is in its active state, it binds to the operator.
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