Professor Hornstein Conducted a Study That Confirmed That Children Who

Professor Hornstein conducted a study that confirmed that children who play with toy guns commit more acts of aggression on the elementary school playground.Professor Kahey conducted a follow-up study and reached the same conclusion.Professor Wiggen's follow-up study did not reach the same conclusions.What can you conclude about Professor Hornstein's research?

A) Her research will need to be replicated many more times before a hypothesis is confirmed.
B) Her results must be incorrect.
C) Because a second researcher confirmed her conclusions,her conclusions are justified.
D) Professor Hornstein's results are accurate,and Professor Wiggen's must have been mistaken.