This question tests the preposition that follows the adjective "ashamed" when expressing shame about something one has done.
- Option A (At): "Ashamed at" is not the standard collocation for this adjective.
- Option B (Of): "Ashamed of" is the standard and correct collocation used to express shame or embarrassment about something, such as a mistake or action.
- Option C (For): "Ashamed for" is used in a different sense, generally to express shame or sympathy on behalf of another person, not for one's own mistake.
- Option D (From): "Ashamed from" is grammatically incorrect in English.
The correct answer is B) Of, so option 2 is the answer.