The correct option is A Argh
Beginning with the rest of the options first, 'Well', as an interjection, is used in various places with various meanings but it clearly does not express a feeling of disgust and so, is not an appropriate word to fill the blank. 'Bravo' on the other hand, is used to express happiness and therefore, it can't be used here. 'Eh' expresses a feeling of surprise and hence, it too can't be used. The most appropriate option the given ones appears to be 'Argh' as it clearly expresses a feeling of disgust or horror, anguish etc.