Which area of the brain stem is in contact with the spinal cord?

Medulla Oblongata

Explanation:

The brain stem is the posterior part of the brain that connects the cerebrum and cerebellum to the spinal cord. It is an area at the base of the brain located between the cerebral hemisphere and the spinal cord. The brain stem is composed of the following in order of inferiority: diencephalon (sometimes included but not main), midbrain, pons, and medulla oblongata.

This parts of the brain stem connects to one another upwardly and downwardly. The medulla oblongata is the lowest part of the brain stem which connects the pons to the spinal cord. It is the part of the brain stem that message is conveyed through to and from the brain and the rest of the body as it is continuous with the spinal cord.

Hence, it is the part of the brain stem that directly comes in contact with the spinal cord.