【名词&注释】
粘连性肠梗阻(adhesive intestinal obstruction)、社会公众(public)、社会影响(social influence)、小肠梗阻(small-bowel obstruction)、结肠梗阻(colon obstruction)、麻痹性肠梗阻(paralytic ileus)、肺动脉瓣(pulmonary valve)、行政主管部门(executive branch)、卫生事件(health event)、食物中毒事件(food poisoning occurred)
[单选题]有关肺动脉瓣(pulmonary valve)口的描述,正确的是
A. 肺动脉瓣(pulmonary valve)由2个瓣叶组成
B. 肺动脉瓣(pulmonary valve)由3个瓣叶和3组小乳头肌组成
C. 肺动脉瓣(pulmonary valve)口由肺动脉瓣(pulmonary valve)环和3个半月形肺动脉瓣(pulmonary valve)组成
D. 肺动脉瓣(pulmonary valve)口直接与右室流入道相连续
E. 肺动脉瓣(pulmonary valve)口向下通过宽大的右室流入道与右室相连