Critical Reasoning (CR) | Re: A certain cultivated herb is one of a group of closely related plants

I agree with your answer. In fact, that is the answer I had in mind.
But when I sawthe solution to the question , it was not at all convincing. I tried to search it on all gmat platforms, but did not find the exact question posted anywhere (though similar ones are there). Did not even have a OA for same. LaterBunuel added the OA which was in line with the solution provided by the first respond received hereurvashis09 . I believe that the herb renders the metals inert in the vicinity of the plant,