The correct option is A Diary entry
The correct format is Option A. 'Your pet dog being sick' is a sad moment for you. It is a personal feeling and everyone may not have their interest in this matter. So, This topic should accounted as a diary entry by an individual. Option B is incorrect as articles are generally found in newspapers for public interest. Option C is incorrect as speech is generally given on an important topic or interest. Option D is incorrect as posters have images or quotes to depict a thought or a feeling.