The correct meaning of the underlined idiom in the sentence:

The Swedish Scientists realized that they had been barking up the wrong tree, is:

A. Shouting at someone unnecessarily.
B. Following the wrong course of action.
C. Arguing for the wrong reason.
D. Behaving in an crazy manner.

Choose the correct answer from the options given below:

B only

The correct answer is Option (2) - B only