Natural selection means that the organisms better adapted to their environment, that is, they have developed the right characteristics/skills/response to the external ambient, have higher chance to survive, making the next generations genetically inherit such acquired surviving characteristics.
These generations will thus have a higher chance of survival, making these species being "naturally selected" as survivors, while those who haven't or are slower in this process, have a higher risk of elimination.
Bacteria reproduce by Binary Fission (also known as "Budding"), a simple process in which many prokatyoric organisms reproduce; it involves cell division after the replication of the nucleoid.
Answer: The correct answer is choice D.
Explanation: We can see on the cladogram that these two are in the same branch and lead to the same common ancestor. These two happen to share the most recent common ancestor, however.