Analyze the options: The first option states that butterflies have an external skeleton called an exoskeleton, which aligns with the characteristics of arthropods. The second option, 'Butterflies lack any form of skeletal support,' is incorrect because arthropods rely on their exoskeleton for structural support. The third option, 'Butterflies have a cartilaginous skeleton similar to sharks,' is incorrect because cartilaginous skeletons are found in vertebrates like sharks, not insects. The fourth option, 'Butterflies have an internal skeleton made of bones,' is also incorrect because insects do not have bones or internal skeletons.