Is it dis ingenuous or ingenuous?

adj. frank, straightforward; simple, innocent, unsophisticated; naive

Sentence with the word ingenuous: He made an ingenuous admission to the teacher that he did not complete his homework as he had gone out with friends the previous evening.

She was getting tired of the child's constant need to ask ingenuous questions.The little girl was in fact ingenuous because she told the truth.

He was not offended by her direct question because her manner was so ingenuous.

An ingenuous person says what she believes ,without any attempt to tailor the expression to the expected audience. Although he insisted he was telling the truth, the smirk on his face led me to think...