Final answer:
The National Park Service was founded in 1916 to conserve park resources and to make them accessible to the public, guided by the philosophy of both preservation and efficient resource management.
Option C.
Step-by-step explanation:
In 1916, the organization founded to conserve park resources and provide their use for the public was the National Park Service.
This establishment came as a result of the conservation movement which gained momentum due to the likes of President Theodore Roosevelt and conservationists such as Gifford Pinchot and John Muir.
The movement focused on the preservation of vast tracts of land for both public enjoyment and the sustenance of natural habitats, and led to the creation of a national park system following the ideologies of both preservation and efficient resource management.
Efforts to establish a balance between the destruction of natural areas and their preservation culminated in the passage of the "National Park System Organic Act," spearheaded by the administration of President Woodrow Wilson.
This legislative act enshrined the principle of maintaining parks "unimpaired for future generations," a core tenet that continues to guide the management of public lands to this day.