Final answer:
The trapezium is the bone that articulates with the first metacarpal of the hand, enabling thumb movement as part of the carpometacarpal joint.
Step-by-step explanation:
The bone that articulates with the first metacarpal is the trapezium. This articulation is part of the carpometacarpal joint of the hand. The trapezium is one of the distal carpal bones and it sits laterally in the row, articulating with several bones: it meets the scaphoid proximally, the trapezoid and capitate medially, and it interacts with the second metacarpal distally. However, its most significant articulation in the context of this question is with the first metacarpal bone of the thumb, which facilitates the thumb's unique range of motion, including its ability to oppose the other fingers.