诊断干细胞癌时,首选的肿瘤标志物()
A.APF
B.PSA
C.hCG
D.AFP
E.CEA
参考答案:A, C, D
There____a banana and two apples on the table.[ ]
A. is
B. are
C. have
D. has
青藏高原上的主要农作物有[ ]
A.青稞、小麦
B.小麦、玉米
C.青稞、玉米
D.青稞、水稻