Answer:
The correct answer is "p18, p21 and p27".
Explanation:
In this experiment, four proteins were blocked and the level of DNA replication was tested in different cell cultures to see which proteins may play a role in cell cycle. Based on the given data we can conclude that p16 is the only protein that appear to have a pivotal role in cell cycle, while p18, p21 and p27 apparently does not. We can conclude this by observing group 7 of cells, were cells have only p16 active and were able to have around 80% of DNA replication.
