【名词&注释】
肺结核(pulmonary tuberculosis)、肺脓肿(lung abscess)、中晚期食管癌(advanced esophageal carcinoma)、吞咽困难(dysphagia)、木质部(xylem)、密切接触史、裸子植物(gymnosperm)、韧皮部(phloem)
[单选题]As a vessel changes course to starboard,the compass card in a magnetic compass().
A. remains aligned with compass north
B. also turns to starboard
C. first turns to starboard then counterclockwise to port
D. turns counterclockwise to port