How is Question 2 an invalid argument?

Hello @Motunrayo-Bamgbose-Martins, We have pretty high standards about what constitutes a valid argument. If the conclusion is not completely guaranteed, then it is not considered valid. While I can't point out any clear reasoning errors in this example, we cannot say with certainty that the conclusion "there is no necessary connection" follows from the premises. It is possible that some research will be found to the contrary. You asked how this affects the main point, which is a very good question. On the LSAT we will be asked to analyze a lot of flawed arguments, some even ridiculous arguments. This does not affect the main point. We still need to take these arguments seriously, and understand their structure so that we can identify premises, conclusions, etc.