Four of the following five are alike in a certain way and so form a group. Which is the one that does not belong to that group?

As per the given above question , we can see that
A, B, C, D, E, F and G, lives on each floor. A lives on fourth floor. E lives on the floor immediately below F's floor. F does not live on the second or the seventh floor. C does not live on an odd-numbered floor.
Hence , C is required answer .