The correct answer is :Bifid rib which is a congenital abnormality of the rib cage and associated muscles and nerves which occurs in about 1.2% of humans. N.B :IT's usually asymptomatic, and are often discovered incidentally by chest X-ray. Effects of this neuroskeletal anomaly can include respiratory difficulties, neurological difficulties, limitations, and limited energy from the stress of needing to compensate for the neurophysiological difficulties.
