Hi Muhammad, It's a passive voice construction. It's saying that the athletic teams brought advantages to the universities. (The teams are the "agents" of the action, meaning they're the ones bringing advantages. The universities are the "patients" or "recipients" of the action, meaning the advantages are brought to them. They are not bringing the advantages.) For such a construction English requires the auxiliary verb "to be," as in the third answer. The first two are active forms of the verb "bring" using different auxiliaries ("can" and "have"). So they don't fit with the sentence, because they make the universities the "agent" of the action, meaning that they are the ones that are bringing the advantages. The phrase "by athletic teams" would not fit with such a sentence. To me #4 also looks technically correct. It's awkward and I would probably write it differently, but strictly speaking it's allowable, unless I'm missing something.