People with Kartagener's syndrome suffer from a variety of ailments, including the intriguing condition known as situs inversus, a reversal of the abdominal and thoracic organs. This condition occurs because of __________.
a defect in immotile cilia that causes them to be motile
mutations that disrupt monocilia function
defective Sonic hedgehog gene
none of the listed reasons
a defect in motile cilia that renders them immotile