The issue with (D) is that it says "in contrast to the standard theory of evolution, the claims ...rest on purely circumstantial evidence," which contradicts the information in the passage that tells us that "evolutionary mechanisms are never observed directly, so we must make do with circumstantial evidence" (lines 46-47), meaning the standard theory of evolution is likewise supported by circumstantial evidence.
Let me know if this helps and if you have any other questions.
