Respuesta :
C. When birds moved into the field, they changed the environment and selected against the blue butterflies
Population of skipper butterflies end up becoming more red butterflies because:-
When birds moved into the field, they changed the environment and selected against the blue butterflies
This is due to Natural Selection
What is natural selection?
It is a mechanism in which the organism who is more adapted to the environment survive and pass there genes to the next generation .
Here due to changing environment blue butterflies were more visible to birds than red one. So the environment favored red butterflies and they lived where as blue one get eliminated.
What is environment?
The surroundings or condition in which a person animal or plant lives or operates
To know more about natural selection here
https://brainly.com/question/9830102
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