下列属于生理碱性肥料的是（）。
A.硫酸铵
B.碳酸氢铵
C.氨水
D.硝酸钙
参考答案：D
.
Mary quickly closed the door of her room _______ her father could reach it to keep him out.
A．before
B．when
C．as
D．while
隐孢子病免疫功能低下者的临床表现为（）
A.可伴电解质紊乱等
B.难以控制腹泻粪量多
C.持续可达数月
D.每天可达数十次水样便
E.起病缓慢、症状重
