ETS Verbal Reasoning RC Question

Hi! Can someone help me with question 10 from the Hard section of Reading Comprehension. I have posted it below with the passage. The correct answer is C, but I picked B. I felt like B was more in line with what the passage stated. Can someone help me understand how to reason between answer choice?

Thank you!

The conclusion of the passage is: that since the under-image face also appears in other van Gogh paintings, the surface painting must be an authentic van Gogh painting.

The conclusion is properly drawn only if we can prove that the under-image face appearing on another canvas of an artist is reliable enough logic to attribute this painting to that artist. This is clearly what option c does.

Option B says this logic of looking for the under-image face in other paintings happened in some other instances but doesn’t really prove anything.

Hope this helps!

That helps a lot, thank you!