6.设 $\mathrm{z}_{1}, \mathrm{z}_{2}$ 是复数,则下列命题中的假命题是
A. 若 $\left|z_{1}-z_{2}\right|=0$,则 $\overline{z_{1}}=\overline{z_{2}}$
B. 若 $z_{1}=\overline{z_{2}}$,则 $\overline{z_{1}}=z_{2}$
C. 若 $\left|z_{1}=z_{2}\right|$,则 $z_{1} \cdot \overline{z_{1}}=z_{2} \cdot \overline{z_{2}}$
D. 若 $\left|z_{1}=z_{2}\right|$,则 $z_{1}{ }^{2}=z_{2}{ }^{2}$