Answer:
A. The seperation of sister chromatids.
Explanation:
During meiosis II the sister chromatids that are in the two daughter cells become separated, leading to the formation of four new haploid gametes.
In the early 1600s, Johannes Kepler proposed three laws of planetary motion. Kepler was able to summarize the carefully collected data of his mentor - Tycho Brahe - with three statements that described the motion of planets in a sun-centered solar system. Kepler's efforts to explain the underlying reasons for such motions are no longer accepted; nonetheless, the actual laws themselves are still considered an accurate description of the motion of any planet and any satellite.
B. Oncogenes. Protooncogenes usually mutate to form oncogenes, which codes for a growth factor that is permanently activated, which leads to excessive cell division.
Hope this helps! :)
I think its O+ but im not sure. Sorry if its correct.