治疗用放射性药物的描述下列哪项错误（）。

A.放射性药物在体内的有效半衰期必须足够长，使病灶能浓聚足够的放射性药物

B.临床病灶有明显症状的患者不适合放射性核素治疗

C.能释放出具有高LET的射线（如α粒子和俄歇电子）的核素，有效杀伤病变细胞的能力强

D.血管生成前病灶用发射β射线或俄歇电子的核素进行治疗

E.亚临床病灶（3～5mm）选择发射β射线或α射线的核素进行治疗

A．Heavy rain triggered floods which caused heavy casualties and damage.

B．Harsh drought had been going on for several years and killed some people.

C．23 people were missing after a storm hit a village in the mountainous province.

D．Authorities were searching for the people who had crossed the border from other countries.