Do evolution take many generations to occur?

All else being equal, the more generations you have the more quickly evolution happens. Usually only laboratory scientists studying quickly reproducing life forms, like single celled creatures and some invertebrates, have the opportunity to see evolutionary change happen before their eyes .

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.

substitution is the answer in this case