Final answer:
The shoulder joint is a ball-and-socket joint and allows the arms to be brought closer together or spread further apart, offering the greatest range of motion among all joints.
Step-by-step explanation:
The joints that allow us to bring the arms closer together or spread them further apart are the ball-and-socket joints located at the shoulder. The shoulder joint, also known as the glenohumeral joint, is the joint with the greatest range of motion in the human body.
Among the types of synovial joints, the ball-and-socket joint allows for a wide range of movements, including rotation in a circle, and forward, backward, upward, and downward motions. This is due to the rounded head of one bone (the ball) fitting into the concave depression (the socket) of another bone. Therefore, the correct answer to the question is option 1) Shoulder joint.
It is important to note that the more mobile a joint, the generally weaker and more susceptible to injury it can be. However, the shoulder joint, while having a vast range of motion, is stabilized by muscles and ligaments.