Knee joint is an example for (a) Ball and socket joint(b) Hinge joint(c) Pivot joint(d) Gliding joint

The correct answer is (b) Hinge joint.

Explanation:

The knee joint is a hinge joint, which means it allows movement in one plane, similar to the motion of a door hinge. In a hinge joint, one bone moves along the surface of another, allowing for bending and straightening movements.

In the case of the knee:

The femur (thigh bone) and tibia (shin bone) meet at the knee joint.
The primary movement is flexion (bending) and extension (straightening).
The knee joint is stabilized by ligaments, tendons, and muscles, which help control the movement and prevent excessive bending.
Other options:

Ball and socket joint (e.g., shoulder, hip): Allows movement in all directions, including rotation.
Pivot joint (e.g., neck): Allows rotation around a single axis.
Gliding joint (e.g., wrists, ankles): Allows sliding movements between bones.
Thus, the knee joint's structure and function classify it as a hinge joint.