The predecessor of square root of 225 is

$\therefore \text{Predeccessor}\text{of}\sqrt{225}=\text{Predeccessor}\text{of}15=14$

A: Successor of square root of 169

=successor of $\sqrt{169}$

=successor of 13 $=14$

B: $\sqrt{196}=\sqrt{14\times 14}$

C: $\sqrt{{\left(12+2\right)}^2}=\sqrt{{14}^2}=14$

D: ${13}^2=169$

So A,B,C are correct.