The answer to your question would be that the sentence that contains three common nouns is the following one: She has never upset an object or as much as brushed a magazine onto the floor. That is, the correct option would be C.
The three common nouns found in the sentence in question are the following ones: object, magazine and floor. A common noun is the generic name for a person, place, or thing in a class or group. As opposed to proper nouns, they are not capitalized.
Figure out your product and then explain it how someone would have to explain it to you to persuade you to want to buy it. Use a technique that you hear on the radio or see on TV. (That should help come up with a fallacy.) Hope this helps.
