Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, from the meandering shape typically found in well-vegetated zones to the braided patters found in areas without deep-rooted vegetation to hold the soil together.
This question is from GMATPrep1, and the correct answer is A. Grammatically, what role does the "from .. to" structure play in the sentence? Is it a verb modifier that describes "changed suddenly"? Is it an absolute phrase?
Streams changed, from A to B.
This question is from GMATPrep1, and the correct answer is A. Grammatically, what role does the "from .. to" structure play in the sentence? Is it a verb modifier that describes "changed suddenly"? Is it an absolute phrase?
Streams changed, from A to B.

















