Select the sentence that suggests that scientists still have NOT perfectly copied spider’s silk.
A: Spiders evolved this process over hundreds of millions of years, Shah said.
B: The latter two parts are held together by molecules called cucurbiturils that serve as ‘handcuffs.’
C: The fibers are extremely strong- though not quite as strong as the strongest spider silks.
D: This means that if they can be produced at scale, they have an advantage over other synthetic fibers, such as nylon.