Three blocks `A,B and C` of masses `4kg,2 kg and 1 kg` respectively, are in contact on a frictionless surface, as shown in the figure. If a force of `14N` applied on the 4 kg block, then the contact force between A and B is
Options:
(a) `2 N`
(b) `6 N`
(c) `8 N`
(d) `18 N`