Analyzing the Context:
The sentence presents a contrast. It states that North America had "hundreds of distinct cultural groups," each with its "own language, mythology, and social mores" (emphasizing diversity). Then, it introduces "the idea of a single 'Native American' culture." The semicolon acts as a strong logical connection, indicating that the diversity mentioned challenges or disproves the idea of a single culture. We need words that convey this sense of disproving or being inconsistent with.
- A. implicated: Means to show (someone) to be involved in a crime or to show (something) to be involved in an event or situation. This doesn't fit the logical relationship of diversity disproving an idea.
- B. belittled: Means to make (someone or something) seem unimportant. While diversity might make the idea seem less plausible, "belittled" is more about devaluing than disproving.
- C. proven: Means demonstrated to be true or valid. This is the opposite of what the context implies (diversity would not prove a single culture).
- D. contradicted: Means to deny the truth of (a statement or theory) by asserting the opposite; to be in conflict with. This fits perfectly, as the diversity is in conflict with the idea of a single culture.
- E. demonstrated: Means clearly show the existence or truth of (something) by giving proof or evidence. Similar to "proven," this is the opposite of what the context implies.
- F. negated: Means to make (something) ineffective; nullify; to deny the existence of. This also fits perfectly, as the diversity effectively nullifies or denies the idea of a single culture.

Both contradicted and negated convey the idea that the diversity disproves or renders invalid the notion of a single Native American culture. They both represent a strong opposition between the stated fact (diversity) and the idea.