Answer :
The implied main idea of the given passage is B. Preserving the natural resources in America's national parks is the main reason they should be conserved.
What is Main Idea?
This refers to the central message of a text that an author wants to convey to his readers.
Hence, we can see that The implied main idea of the given passage is B. Preserving the natural resources in America's national parks is the main reason they should be conserved.
This is because it is stated that the national park was a national heritage that showed the country in all its glory as it demonstrates their democracy.
Read more about main ideas here:
https://brainly.com/question/24572492
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