步测CDE级GPS网时，可是测区范围的大小实行分区观测，分区观测时，相邻分区的公共点至少应有（）个。
A、2
B、3
C、4
D、5
参考答案：C
---- It took me nearly 5 years to make a breakthrough in my field.
---- Well, you know what people say. _________.
A．There is no smoke without fire.
B．Practice makes perfect.
C．All roads lead to Rome.
D．No pains, no gains.
原发性痛风患者的遗传属于（）
A.酶的缺陷
B.多基因遗传
C.白细胞
D.红细胞
E.单基因遗传
