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.
Blank (i) Blank (ii) Blank (iii)
A. lacked D. problematic G. being revived in
B. discounted E. unnecessary H. dropping out of
C. employed F. straightforward I. losing out to