If $z_1,z_2$ are any two complex numbers and $a,b$ are two real numbers, then $|az_1-bz_2|^2+|bz_1+az_2|^2=?$

Question

(A) $(a^2+b^2)(|z_1|^2+|z_2|^2)$

(B) $(a+b)(|z_1|^2+|z_2|^2)$

(C) $(a^2+b^2)(|z_1|+|z_2|)$

(D) $(a^2+b^2)(|z_1\overline z_2|+|z_2\overline z_1|)$