1[单选题]
现有订单表orders, 包含数据如下表。若查询既订购了产品P01，又订购了产品P02的顾客编号，可以执行以下（）sql语句。
cid (顾客编号) Pid （产品编号）
C01 P01
C01 P02
C02 P01
C03 P02

A.select distinct(cid) from orders o1 where o1.pid in ('p01','p02')

B.select distinct(cid) from orders o1,orders o2 where o1.pid='p01' and o2.pid='p02' and o1.cid=o2.cid

C.select distinct(cid) from orders o1 where pid='p01' and cid in (select cid from orders where pid ='p02')

D.select distinct(cid) from orders o1,orders o2 where o1.pid='p01' and o2.pid='p02'