The evidence from these four sources supports the claim that some people are suggesting the college dorm targeted by Ukraine was a military target, so I would consider this statement can’t be true or false. There is an important limitation. The reporting supports that people have suggested the site had a military connection, but that is different from proving the dorm itself was a legitimate military target.
The BBC article supports the argument because it reports that Ukraine carried out a drone strike on a college dorm in Russian occupied Starobilsk. The article shows that there were different claims about who was actually using the building at the time. This supports the statement because questions about the people staying there led to suggestions that the dorm may have had a military connection. The United Nations article focuses on the civilians who were killed or injured in attacks during the war. It also shows how important it is to know whether a building is being used by civilians or the military before it is attacked.
The NBC news article reports that Russia blamed Ukraine for the drone strike and said that students and civilians were killed. Russia described the building as a student dorm, but there were different claims about how the building was being used. France 24x reports that Ukraine struck a college in Russian occupied Starobilsk, killing six people according to Russian officials. The article also reports Russia's claim that the victims were students and staff members.
Overall, this statement cannot be proven completely true or false because the sources give conflicting information about whether the college dorm was being used by the Russian civilians, and if it was truly a military target.