In the text,
"availability" (l.5) means difficult to be obtained.
In the text,
threaten" (l.32) is synonymous with menace.
According to the text, it can be deduced that
"enormous" (L.15) is the same as large. 
“Although” (line 3) introduces an idea of contrast. The idea introduced by the discourse marker is correctly stated in
Based on the text above, judge the following items.
"In fact" (l.16) is the same as As a matter of fact.
Based on the text above, judge the following items.
"source" (l.20) means fountain.
No texto, due to significa:
In the text, the expression "drop in the ocean" (l.33-34) means
In the sentence “…while power dams were left behind with a 14.7 percent share.” (lines 10-11), the word “while”
Based on the meanings in the text, mark the only option in which the two words are antonymous.
