稻田里的杂草和水稻之间形成的关系是[ ]
A.竞争
B.捕食
C.合作
D.寄生
A
Both the summer and winter Olympic Games every four years.
A.break out
B.come about
C.happen
D.take place
迅速判断患者心脏停搏的方法是
A.扪脉搏B.听心音C.扪颈动脉或股动脉搏动D.测血压E.心电图检查