Which one of the following is an acceptable assignment of photographers to the two graduation ceremonies?

I had lots of trouble with his game but when I watched the videos from Matt and the other instructor what I noticed is that they follow inferences from the most restricted rule down to the least. Could we get a video (and hopefully in a quick response to this post) a hierarchy of rules sorted by level of restriction and how to notice which rules are more restrictive than others? I often hear the terms "most" and "least" restricted rules but I can't determine which ones are more or less restrictive than others. I know the most restrictive ones constrain the amount of worlds the variables can be arranged in such as rule 1 in this game. But would the next most restrictive rule be the ones with the most necessary conditions?