Close to the elbow, the ulna has a bony process, the olecranon process, a hook-like structure that fits into the olecranon fossa of the humerus. This prevents hyperextension and forms a hinge joint with the trochlea of the humerus. There is also a radial notch for the head of the radius, and the ulnar tuberosity to which muscles attach.\n\nBased on this passage, where does the ulna articulate with the humerus?
Stream of thoughts:
the olecranon fossa
The relevant information to answer the above question is: Close to the elbow, the ulna has a bony process, the olecranon process, a hook-like structure that fits into the olecranon fossa of the humerus.

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Thus, the answer is the olecranon fossa