Does St John's Wort Have a Significant Effect in Treating Major

Multiple Choice

Does St. John's wort have a significant effect in treating major depression? A study looked at 340 adult outpatients suffering from major depression as measured by their HAM-D score, randomly assigning each subject to either a placebo, St. John's wort, or a second active treatment for comparison.
The study found the difference in treating major depression as measured by improvement in HAM-D scores between St. John's wort and the placebo was not statistically significant. This means that:

A) we cannot make a 95 percent confidence statement.
B) a difference this big could easily occur just by chance even if St. John's wort does no better than the placebo.
C) the placebo makes no difference in the subjects' depression.
D) the study was badly designed.