Well, I need the chart first of all, but second, If you have to find out which one is closely related to A, just take the amino acid sequence and compare the sequence to each organism, and which ever one has the most related sequences, is the closely related organism.
D Because the law of superposition the younger rocks are ontop of the older rocks
Because good researchers rely on first hand account or better said primary evidence. The reason why they rely on primary evidence is because it is usually the most reliable. Much more so than secondary or even tertiary evidence. This enables them to understand the history of a certain topic better.