Although the author does have a slightly negative attitude toward research focused solely on methods brought from outside North America, the main purpose of the passage is broader than this criticism. The author focuses instead on supporting research into indigenous knowledge.

This doesn’t capture the author’s support for research into indigenous knowledge. The author’s intention isn’t merely to describe differences between approaches; it’s to support a particular approach.

Tempting, but not accurate, because the author doesn’t “propose” a “novel” (new) solution. Rather, the author identifies a potential solution that is being pursued by researchers and experts. The author isn’t the one who comes up with a new solution.

“Definitive” is too strong. The author never suggests that the solution is definitive or otherwise certain to work. Rather, the author uses the phrase “possible solution.”

This best captures the author’s purpose, which is to support research into indigenous knowledge of heirloom crops as a way to solve the problem of North American crops’ eroding genetic base.