Open the brackets and write the sentence using the Present Perfect or the Past Simple. Use a short negative form. She ... (not/eat) anything since this morning.

The correct answer is: hasn't eaten.

Explanation:

The sentence requires the Present Perfect tense because it refers to an action that started in the past and continues to have relevance to the present (since this morning).

The negative form of Present Perfect is constructed using "has/have + not + past participle". Since the subject is "She", we use "has". The past participle of "eat" is "eaten". Therefore, the correct form is "has not eaten" or, in a short form, "hasn't eaten".