Answer:
(B) an under allocation of resources to neuromuscular disease research, relative to the efficient level.
Step-by-step explanation:
Based on this passage, we can assume that the public in general is not interested in neuromuscular disease. If this is the case, this subject is unlikely to create much profit (and thus interest) for the private sector. If medical research in this area were left exclusively to the private market, it is likely that there would be an under allocation of resources to neuromuscular disease research, relative to the efficient level.