The formula for the kinetic frictional force is given as
[tex]f_k=\mu_kmg[/tex]*Here m is the mass of the block
*Here g is the acceleration due to the gravity
From the above expression, the mass of the object and the value of the acceleration due to gravity is constant. The value of the coefficient of kinetic friction remains the same for all the surfaces. Therefore, the kinetic friction is constant but less than the maximum static fritction.
Hence, the correct option is (C)
