Final answer:
The sagittal suture connects the greatest number of bones, joining the right and left parietal bones on the top of the skull.
Step-by-step explanation:
The suture that connects the greatest number of bones is the sagittal suture. The sagittal suture runs along the midline at the top of the skull, joining the right and left parietal bones. On the posterior skull, it terminates by joining the lambdoid suture, which joins the occipital bone to the right and left parietal and temporal bones. This suture is named for its upside-down "V" shape, resembling the Greek letter lambda. Therefore, the sagittal suture connects three bones, while the coronal suture connects two bones and the squamous suture connects two bones.