What does the reference line at lift = 1 corresponds to?

Refer to the lift chart:

What does the reference line at lift = 1 corresponds to?
A . The predicted lift for the best 50% of validation data cases
B . The predicted lift if the entire population is scored as event cases
C . The predicted lift if none of the population are scored as event cases
D . The predicted lift if 50% of the population are randomly scored as event cases

View Answer

Answer: B