Question

main support ligament of c1 (atlas), arches across of atlas, branches up and down to become cruciform ligament alar ligament posterior longitudinal ligament transverse ligament ligamentum flavum

Explanation:

The transverse ligament of the atlas is the main support ligament of C1 (atlas). It arches across the atlas. When it combines with the alar ligament, it forms the cruciform ligament.

• The alar ligament connects the dens of the axis to the occipital bone and is not the main support ligament of C1.
• The posterior longitudinal ligament runs along the posterior surface of the vertebral bodies in the spinal canal and is not specific to C1 as the main support.
• The ligamentum flavum connects adjacent vertebral laminae and is not related to the description of the main support of C1 and formation of the cruciform ligament.

Answer:

Transverse Ligament