Your Broker Suggests That You Can Make Consistent,excess Profits by Purchasing

Multiple Choice

Your broker suggests that you can make consistent,excess profits by purchasing stocks on the 20^th of the month and selling them on the last day of the month.If this is true,then:

A) the market is only semi strong-form efficient.
B) the market violates even weak-form efficiency.
C) insiders will be the only investors to profit.
D) prices follow a random walk.