The answer choice that might be considered a key supporting detail that a writer would use in an objective summary for "Principles of Conservation" by Gifford Pinchot is c. It applies as much to the subject of food roads as to waterways, and the training of our people in citizenship is as germane to it as the productiveness of the earth.
This refers to the use of evidence that shows that a claim is valid with the use of factual information or statistics.
Hence, we can see that the answer choice that might be considered a key supporting detail that a writer would use in an objective summary for "Principles of Conservation" by Gifford Pinchot is c. It applies as much to the subject of food roads as to waterways, and the training of our people in citizenship is as germane to it as the productiveness of the earth.
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