A cam and oscillating follower mechanism is shown in the figure below. The Mobility of the mechanism is

Correct option is C

​$$\textbf{Gruebler’s Equation (Planar):} \\M = 3(n - 1) - 2j_1 - j_2 \\\\\text{Where:} \\M = \text{mobility (degree of freedom)} \\n = \text{number of links (including the frame)} \\j_1 = \text{number of lower pairs (1 DOF joints like revolute or prismatic)} \\j_2 = \text{number of higher pairs (like cam-follower contact – 1 DOF but special case)}$$

$$n = 3 \quad \text{(Cam, follower, frame)} \\j_1 = 2 \quad \text{(2 revolute joints)} \\j_2 = 1 \quad \text{(cam-follower contact)} \\\\M = 3(3 - 1) - 2(2) - 1 = 6 - 4 - 1 = \boxed{1}$$​​​