Answer:
1. A
2. A, B, E, C, D
3. D
4.The most recent common ancestor for F, I, H and J is B.
G is more distinct from F, I, H, and J than they are from one another
Step-by-step explanation:
1. A is the most recent common ancestor because it is the last species from which all the other species diverged. After A, there are two lineages coming from B and E, therefore, A is the last most recent common ancestor for all the species.
2. The species that are not extinct are those that are not represented at the top (present) of the tree. Therefore, C, D, B, A and E are all extinct, whereas G, J, H, I and F are modern species.
3. J and H diverged from species D, which itself diverged from B. Therefore, H and J share D as their most recent common ancestor.
4. The most recent common ancestor for F, I, H and J is B. - After species B, C and D diverged. From C, F and I formed, and from D, H and J formed. Therefore, the most recent common ancestor for F, I, H and J is B.
G is more distinct from F, I, H, and J than they are from one another. G diverged from the others a longer time ago than they diverged from one another. When A diverged into B and E, G was produced from E, whereas all the other species came from B. This means they are more related to one another than G is related to each of them.