Q18

[JackelineZ38]

Can someone show me where they found evidence for the correct answer choice A?

[Misti Duvall]

Sure! It's in the second paragraph, starting with middle of the paragraph, where it says "[h]owever, no known peptide was able to bind..." So Belcher and Hu grew their own peptides (next sentence after that). Then the last sentence of that paragraph says they "developed additional related peptides."

So it's fair to say that if no known peptides could do the job, so they grew their own and then developed additional related peptides, at least the additional related ones didn't exist in nature.