The most likely observation that future scientists would make about the wings of fossilized bats and pterosaurs is:
A Both sets of fossils would show similar structures and bone material that were suited for flight.
This is because both bats and pterosaurs evolved adaptations for flight, resulting in similar functional structures despite being from different evolutionary lineages (bats are mammals, while pterosaurs are flying reptiles). This phenomenon is known as convergent evolution, where different species develop similar traits independently due to adapting to similar environments or lifestyles.