Answer :
The sentence which describes a monarch butterfly as a living system that is complex is that it has four distinct life stages: egg, larva pupa, and adult and is denoted as option A.
What is a Complex system?
This is referred to as a system which has different types of components which are interconnected or interrelated with one another and in this case are the four distinct life stages of a monarch butterfly.
They undergo complete metamorphosis which is characterized by the development from the egg to the larva pupa, and adult stages thereby making it a part of a more complex system.
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