Final answer:
The human hand's dexterity is attributed to the freely movable joint of the thumb, which has a saddle joint allowing versatile movements.Option 1 is the correct answer.
Step-by-step explanation:
The human hand has greater dexterity than the forepaw of any animal principally because of the freely movable joint of the thumb. This mobility is enabled by a special type of joint known as a saddle joint, found between the first metacarpal bone of the hand and one of the carpal bones in the wrist. This joint configuration allows the thumb to move toward and away from the index finger as well as to cross over the palm. In contrast to other joints in the upper limb like the wrist, elbow, or shoulder that also contribute to hand function, the thumb's saddle joint is key to the specialized movements that permit intricate manual tasks.
The exceptional dexterity of the human hand, surpassing that of any animal's forepaw, can be attributed primarily to the unique mobility of the thumb. This unparalleled flexibility is made possible by a distinctive joint type known as a saddle joint, located between the first metacarpal bone of the hand and a carpal bone in the wrist. The saddle joint design facilitates a broad range of movements, allowing the thumb to pivot towards and away from the index finger and even cross over the palm. Unlike other joints in the upper limb, such as the wrist, elbow, or shoulder, the saddle joint of the thumb plays a pivotal role in executing intricate manual tasks by enabling specialized and precise movements.