$.$ If the predictions of the classifier f and its decision boundary w $$ x $+$ b $=0$ are shown

in Figure $2,$ which one below can be a possible solution of weight vector w and bias b$?$

A$.$ w $=(+1,0),$ b $=1.$

B$.$ w $=(1,0),$ b $=+1.$

C$.$ w $=(+1,0),$ b $=+1.$

D$.$ w $=(0,1),$ b $=1$