题目55.(单选题)对于复数z，z^2=|z|^2的充要条件是 ( ).A. z的实部为零B. z的虚部为零C. z=0D. 实部虚部皆不为零55.(单选题)对于复数z，$z^{2}=|z|^{2}$的充要条件是 ( ).A. z的实部为零B. z的虚部为零C. z=0D. 实部虚部皆不为零题目解答答案B. z的虚部为零