Hey!
An article is piece of writing included with others in a newspaper, magazine, or other publication. Those can be academic, laboral or just personal.
Now, the subject of an article can automatically limit the timeliness, the audience and purpose. The subject acts like a border to your article and you will have to respect that limit. For instance, every article has a subject, but it will be conditioned by the subject of the writing piece; and, when writing, you have to identify your audicience and it has to be closed relationed with your subjects, because there are some topics for specific public.
In that sense, the only aspect a subject of an article can not limit is A: effectiveness. A topic by itself does not do anything, it is the way of presenting and writing about it. In addition, there is no any way to know if the article will produce the expected effect on the readers just because of the topic.
Hope this helps!
The answer to this question, is this is something that YOU have to do YOURSELF. It claims that this is your story and that you need to have some fun with it. Basically asking for people to write it for you and then using their stories to answer your question is cheating. Some people on this website are asking for you to explain the answer and help them understand, not just hand the answers to them. I'm sorry if this comes off as rude, but someone could catch you cheating.
The main thing that this question is asking is which sentence does not have a formal tone. A formal tone for research writing usually means using more professional (instead of casual, everyday) language and free of your own opinions.
This means choice D is inappropriate because it is opinionated. Using "I think" is not formal tone.
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Answer: D) I think one of the most frustrating things about owning a cat is that they don't obey many commands.
He smacked him in the face
The appropriate answer would be C. It could lead to other health issues.