Describe the relationship between the amount of movement a joint allows and it’s stability

The amount of movement available at a particular joint of the body is related to the functional requirements for that joint. Thus immobile or slightly moveable joints serve to protect internal organs, give stability to the body, and allow for limited body movement. Mobility: The ability to move freely and easily. Stability: The ability of the body to maintain postural equilibrium and support joints during movement. When the joints are looked at individually, each joint can be classified by their main responsibility. Joint Stability

Shape of articular surfaces (how close they fit) Strength and tension of capsule and ligaments (dependent on position) ... Disuse, causing decrease in synovial fluid, flexibility of ligaments and tendons, and muscle atrophy. Gravity and atmospheric pressure.
A joint is a place where two or more bones meet and is also called an articulation. Synovial joints (freely movable joints) allow us the free movement to perform skills and techniques during physical activity. They connect bone to bone and help keep the joint together. ...
Joint stability depends on several neuromuscular factors, including the strength and coordination of the joint-related muscles as well as proprioception (the ability to sense the position and movement of the limb). hip-joint
Shape, Size and Arrangement of Articular Surfaces

In contrast, the acetabulum of the pelvis fully encompasses the femoral head, and this makes the hip-joint far more stable. However, whilst the hip is more stable, the shoulder has a greater range of movement. The most important factor in joint stability is the depth of the articular surface. The deeper the articular surface, the more stable the joint, but it seems that the strength of the muscles that cross the joint is the most important factor. In most joints, muscle tone is the major factor controlling stability. For example, the muscle tone of the short muscles around the shoulder joint keeps the hemispherical head of the humerus in the shallow glenoid cavity. Without the action of these muscles, very little force would be required to dislocate this joint.

Your answer is going to be c. 

10% more body fat than is recommended i believe