The angular momentum of a particle about $o$ is varying as $L = 4t+8$ (SI units) . When it moves along straight line $y= x-4$(x,y in maters) . The magnitude of force acting on the particle would be

Question

$$\begin {array} {1 1} (a)\;1N & \quad (b)\;2N \\ (c)\;\sqrt 2 N & \quad  (d)\;\sqrt 3 N \end {array}$$