B
Music critic: How well an underground rock group' s recordings sell is no mark of that group' s success as an underground group. After all, if a recording sells well, it may be because some of the music on the recording is too trendy to be authentically underground; accordingly, many underground musicians consider it desirable for a recording not to sell well. But weak sales may simply be the result of the group' s incompetence. Which one of the following principles, if valid, most helps to justify the music critic's argument?
A: An underground rock group is successful as an underground group if the group is competent but its recordings nonetheless do not sell well.
B: An underground rock group is unsuccessful as an underground group if it is incompetent or if any of its music is too trendy to be authentically underground, or both.
C: For an underground rock group, competence and the creation of authentically underground music are not in themselves marks of success.
D: Whether an underground group's recordings meet criteria that many underground musicians consider desirable is not a mark of that group's success.