问题
选择题
A new kind of drug ___ ___ to cure H7N9 bird flu by the scientists and they are hopeful that they will succeed in a couple of weeks.
A．has been developed
B．is being developed
C．is developing
D．has developed
答案
B
题目分析：句意：一种新的药物正在被科学家开发来治疗H7N9禽流感，他们希望他们会在几个星期后成功。从they are hopeful that they will succeed in a couple of weeks. 可知是正在开发，而且drug和develop是被被动关系，选B。