Dr. Moretti recently published a paper on his therapy work with 10 patients whom he said benefitted ...

Dr. Moretti recently published a paper on his therapy work with 10 patients whom he said benefitted greatly from psychoanalysis.  The patients all suffered from moderate depression and were in treatment for 6 months. Dr. Morettis research has come under intense scrutiny as other clinicians and researchers have not been able to consistently find the same results in their patients. This lack of research consistency is a problem for which of the six principles of scientific thinking?
A) falsifiability
B) replicability
C) Occams Razor
D) ruling out rival hypotheses