C

To match the statements in Column I with the figures in Column II, we need to analyze the scenarios depicted in the images.
(a) Magnitude of frictional force is maximum.
In the fourth figure, both blocks are acted upon by large opposing forces (8N on the 2kg block and 20N on the 4kg block). The frictional force must balance the net force to prevent relative motion, making it maximum. Hence, this corresponds to (s).

(b) Magnitude of friction force is least.
In the second figure, only the 2kg block is acted upon by a force of 12N, and the relation of forces indicates that friction is at a minimum here because the force is only acting on the top block. This corresponds to (q).

(c) Friction force on 2 kg block is towards right.
In the first figure, the 4kg block is being pulled right by 12N. Consequently, the friction on the 2kg block (which precedes it) also acts towards the right to prevent slipping. Hence, this corresponds to (p).

(d) Friction force on 2 kg block is towards left.
In the third figure, both blocks are being pulled right with 6N each, which creates a net leftward friction force on the 2kg block to keep it from slipping off the 4kg block. Hence, this corresponds to (r).
Therefore, the correct matches are:
- (a) - (s)
- (b) - (q)
- (c) - (p)
- (d) - (r)
According to the matching logic, the correct answer is C.