The Joint Known as the "Wrist" Is the Radiocarpal Joint

Multiple Choice

The joint known as the "wrist" is the radiocarpal joint.Why is the ulna not considered to be part of this joint?

A) There is no articular cartilage at the distal end of the ulna.
B) The ulna is fused to the carpals,preventing true articulation.
C) There is an articular disc between the ulna and the radiocarpal joint.
D) The radiocarpal joint is condylar,but the ulnar surface is planar.
E) The ulnar collateral ligament does not extend to the carpals.