Which medical root denotes a curvature that may cause misalignment?

The root "scoli/o" specifically refers to curvature of the spine, often seen in conditions such as scoliosis, which involves an abnormal lateral curvature that can lead to misalignment of the vertebral column. This condition can affect posture and overall spinal health, causing various complications if left untreated.

In contrast, "kyph/o" pertains to a forward bending or hunching of the spine, typically associated with kyphosis, which also involves a curvature but is different from the lateral curvature denoted by "scoli/o". The root "lith/o" relates to stone or calcification, often in the context of organs or tissues, and does not address spinal alignment or curvature. "Fibr/o" refers to fibrous tissue and is unrelated to curvature or misalignment in the spine.

Thus, "scoli/o" is the most appropriate choice as it directly indicates a spinal curvature that can lead to structural misalignment in the body.