Referring the graphs, which of the following is/are correct

Option (a) is correct because at 3, force is opposite to displacement.At (b), u is minimum.Option (b) is incorrect because at 2, there is net force and hence no equilibrium.Option (c) is correct because at 1, 3 and (b) force is zero.du At (b), dudx=−F=0Option (d) is correct. Positive work is done after position 1, hence KE will increase. So KE is least at 1.