Can you explain _____ most deserts are located near the west coast of the continents? [ ]

A. why is it that

B. why it is that

C. how it is that

D. how is it that

男，39岁。因患风心病近期多次到一医院就诊，准备做换瓣手术。近3天来发热，体温达38℃以上，头痛、关节痛。轻微干咳，无痰来就诊。查体：体温38℃，肺部检查呼吸音清，未闻及啰音。白细胞0.9×10⁹/L，胸部X线检查显示左肺下叶呈网状改变。根据病史，应首先考虑

A．肺结核

B．支气管炎

C．上呼吸道感染

D．细菌性肺炎

E．传染性非典型肺炎