Unquestionable (adjective)

Not open to doubt or dispute.

Origin:

From the prefix "un-" meaning "not" and the verb "question" meaning "to ask or inquire".

Examples:

1. The evidence was so strong that the defendant's guilt was unquestionable.
2. The authority of the government is an unquestionable fact.
3. The quality of the product is unquestionable, it is the best in the market.
4. The scientist's credentials were unquestionable and his research was highly respected.
5. The beauty of the natural wonder was unquestionable, it was breathtaking.