Let `a ,b ,cR_0` and each of the quadratic equations in `x ,x^2+2(a^2+b^2)x+(b^2+c^2)^2=0` and `x^2+2(b^2+c^2)x+(c^2+a^2)^2=0` has two distinct real roots. Then equation `x^2+2(c^2+a^2)x+(a^2+b^2)^2=0` ha Two distinct positive real roots Two equal real roots Two distinct negative real roots (4) No real roots