Ankle joint is
A. Pivot joint
B. Ball and socket joint
C. Hinge joint
D. Gliding joint

Hint: A synovial joint situated in the lower limb is the ankle joint (or talocrural joint). The bones of the leg (tibia and fibula) and the foot (talus) form it. Functionally, it is a joint of the hinge form, allowing dorsiflexion and foot plantar flexion.

Complete answer: A hinge joint is a common form of a synovial joint that comprises the joints of the ankle, elbow, and knee. Hinge bones are joined within two bones where the bones can only move along one axis to bend or stretch. The best examples of hinge joints are the Interphalangeal joints of the hand and those of the foot and the joint between the humerus and ulna. The knee is the largest hinge joint in the human body.
a) Pivot joint: Pivot joints are a type of synovial joints that permit axial rotation, also known as rotary joints. Inside a ring created by the concave surface of a second bone and an adjoining ligament, the moving bone rotates.
b) Ball and socket joint: The joint of the ball and socket (or spheroid joint) is a type of synovial joint in which one rounded bone's ball-shaped surface fits into another bone's cup-like depression. The distal bone is able to move along an infinite number of axes that have a single core in common.
c) Gliding joint: A gliding joint is a common type of synovial joint developed between bones that meet on flat or nearly flat articular surfaces, also known as a plane joint or planar joint. Gliding joints allow the bones to glide in either direction along the joint plane, past each other.
Hence, the correct answer is option C.

Note: A hinge joint is a type of synovial joint that occurs throughout the body and is used mainly in one plane to enable movement. The hinge joint consists of two or more bones with articular surfaces that are covered by hyaline cartilage and lubricated by synovial fluid. Muscles, ligaments, and other connective tissues, such as the joint capsule, support each hinge joint.