The difficulty for nineteenth-century advocates of the claim that forests helped regulate climate was that their argument (i)____________ historical anecdote and observations. Proving the forest-climate link through verifiable and experimental scientific means rather than observation was (ii)____________ for these individuals, a situation that eventually led to the link (iii)____________ justifications for forest conservation. A. lacked B. problematic C. being revived in D. discounted E. unnecessary F. dropping out of G. employed H. straightforward I. losing out to