The correct option is D Synovial joint
A joint in the human body is a connection between the tissues, cartilages and bones. Synovial joints are characterised by the presence of a fluid filled in the synovial cavity, between the articulating surfaces of the two bones. Such an arrangement allows considerable movement by reducing friction between bones. These joints help in locomotion and many other movements. The joint between malleus and incus is incudomalleolar joints which are a type of small synovial joint. Thus, the correct answer is option D.