Which of the following is the largest foramen of skull?
The foramen magnum is the largest foramen of the skull. It opens upwards into the posterior cranial fossa, and downwards into the vertebral canal. It is oval in shape, being wider behind than in front  where it is overlapped on each side by the occipital condyles.
Foramen lacerum
Foramen magnum
Foramen ovale
Foramen spinosum