组成病毒的核酸是（）。
A.RNA
B.DNA
C.DNA或RNA
D.DNA和RNA
E.以上都不是
参考答案：C
解析：病毒一般以病毒颗粒或病毒子的形式存在，病毒颗粒极其微小，测量单位为纳米（nm），用电子显微镜才能观察到，完整的病毒颗粒主要由核酸和蛋白质组成，结构简单，表现为无完整的细胞结构，仅有一种核酸作为遗传物质。因此，组成病毒的核酸是DNA或RNA。
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