早期癌（食道、胃、肠、肝）
参考答案：
是指组织仅限于粘膜层，未浸及肌层。预后良好。
— Don't you know your computer has been infected with viruses?
— Really, no wonder it hasn't ________ as well as before. [ ]
A. appeared
B. operated
C. managed
D. controlled
